hall florida argued march decided may held eighth fourteenth amendments forbid execution persons intellectual disability see atkins virginia hall asked florida state vacate sentence presenting evidence included iq test score denied motion determining florida statute mandated show iq score permitted present additional intellectual disability evidence state rejected hall appeal finding state threshold constitutional held state threshold requirement interpreted florida unconstitutional pp eighth amendment reaffirms duty government respect dignity persons roper simmons prohibits execution persons intellectual disability legitimate penological purpose served executing intellectually disabled atkins prohibiting executions also protects integrity trial process individuals face special risk wrongful execution likely give false confessions often poor witnesses less able give meaningful assistance counsel determining whether florida intellectual disability definition implements principles atkins holding proper consider psychiatric professional studies elaborate purpose meaning iq scores scores relate atkins consider several implemented atkins pp florida rule disregards established medical practice face florida statute consistent views medical community discussed atkins conclusions reached defines intellectual disability existence concurrent deficits intellectual adaptive functioning long defining characteristic intellectual disability see atkins supra nothing statute precludes florida considering iq test standard error measurement sem statistical fact reflecting test inherent imprecision acknowledging individual score best understood range five points either side recorded score interpreted florida however florida rule disregards established medical practice two interrelated ways takes iq score final conclusive evidence defendant intellectual capacity experts consider evidence relies purportedly scientific measurement defendant abilities refusing recognize measurement inherent imprecision professionals long agreed iq test scores read range florida uses test score fixed number thus barring consideration relevant evidence deficits adaptive functioning including evidence past performance environment upbringing pp rejection strict cutoff vast majority consistency trend roper supra toward recognizing sem provide strong evidence consensus society regard strict cutoff proper humane nine mandate strict iq score cutoff thus individual hall position deemed automatically eligible death penalty direction change consistent since atkins many passed legislation comply constitutional requirement persons intellectual disability executed two appear set strict cutoff least others either abolished death penalty passed legislation allowing defendants present additional intellectual disability evidence iq score every state legislature save one considered issue atkins whose law interpreted courts taken position contrary florida pp atkins acknowledges inherent error iq testing provides substantial guidance definition intellectual disability play critical role advancing protections atkins providing understanding intellectual disability measured assessed atkins give unfettered discretion define full scope constitutional protection clinical definitions intellectual disability express terms rejected strict iq test score cutoff long included sem fundamental premise atkins see nn fleeting mention florida citation listing outlawed execution intellectually disabled signal atkins approval state current understanding law yet interpreted florida require strict cutoff pp defendant iq test score falls within test acknowledged inherent margin error defendant must able present additional evidence intellectual disability including testimony regarding adaptive deficits legal determination intellectual disability distinct medical diagnosis informed medical community diagnostic framework particular help alternative intellectual disability definition presented placed substantial reliance medical profession expertise pp reversed remanded kennedy delivered opinion ginsburg breyer sotomayor kagan joined alito filed dissenting opinion roberts scalia thomas joined opinion notice opinion subject formal revision publication preliminary print reports readers requested notify reporter decisions washington typographical formal errors order corrections may made preliminary print goes press freddie lee hall petitioner florida writ certiorari florida may justice kennedy delivered opinion held eighth fourteenth amendments constitution forbid execution persons intellectual disability atkins virginia florida law defines intellectual disability require iq test score less test scores prisoner deemed iq exploration intellectual disability foreclosed rigid rule holds creates unacceptable risk persons intellectual disability executed thus unconstitutional february freddie lee hall petitioner accomplice mark ruffin kidnaped beat raped murdered karol hurst pregnant newlywed afterward hall ruffin drove convenience store planned rob parking lot store killed lonnie coburn sheriff deputy attempted apprehend hall received death penalty murders although sentence coburn murder later reduced account insufficient evidence premeditation hall florida per curiam hall argues executed intellectual disability previous opinions employed term mental retardation opinion uses term intellectual disability describe identical phenomenon see rosa law stat changing entries code mental retardation intellectual disability schalock et al renaming mental retardation understanding change term intellectual disability intellectual developmental disabilities change terminology approved used latest edition diagnostic statistical manual mental disorders one basic texts used psychiatrists experts manual often referred initials dsm followed edition number see american psychiatric association diagnostic statistical manual mental disorders ed hall first sentenced yet ruled eighth amendment prohibits imposing death penalty persons intellectual disability see penry lynaugh time florida law consider intellectual disability statutory mitigating factor held capital defendants must permitted present nonstatutory mitigating evidence death penalty proceedings hitchcock dugger hall resentenced hall presented substantial unchallenged evidence intellectual disability school records indicated teachers identified numerous occasions entally retarded app hall prosecuted different earlier crime lawyer matter later testified lawyer ould really understand anything hall said respect murder trial given case hall counsel recalled hall assist defense mental level much lower age best comparable lawyer daughter brief petitioner number medical clinicians testified professional opinion hall significantly retarded app mentally retarded levels understanding typically seen toddlers explained detail individual ability lack ability adapt adjust requirements daily life success lack success central framework followed psychiatrists professionals diagnosing intellectual disability see hall siblings testified something wrong child app hall slow speech slow learn walked talked long brothers sisters great difficulty forming words hall upbringing appeared make deficits adaptive functioning severe hall raised words sentencing judge horrible family circumstances imaginable eachers siblings alike immediately recognized hall significantly mentally retarded retardation garner sympathy mother rather caused much scorn befall hall onstantly beaten made simple mistakes ibid mother strap hall bed night rope thrown rafter morning awaken hall hoisting whipping belt rope cord ibid hall beaten ten fifteen times week sometimes mother tied sack swung fire beat buried sand neck legs held gun hall poked sticks hall florida barkett dissenting jury notwithstanding testimony voted sentence hall death sentencing adopted jury recommendation found substantial evidence record support finding freddie lee hall mentally retarded entire life app yet also suspect ed defense experts guilty professional overkill othing experts testified explain psychotic person formulate plan whereby car stolen convenience store robbed sentencing went state even assuming expert testimony accurate learning disabilities mental retardation mental difficulties used justify excuse extenuate moral culpability defendant cause hall sentenced death florida affirmed concluding hall argument mental retardation provided pretense moral legal justification merit hall chief justice barkett dissented arguing executing person intellectual disability violated state constitution prohibition cruel unusual punishment ruled eighth amendment prohibited execution persons intellectual disability atkins virginia november hall filed motion claiming intellectual disability executed five years later florida held hearing consider hall motion hall presented evidence intellectual disability including iq test score hall received nine iq evaluations years scores ranging brief respondent sentencing excluded two scores evidentiary reasons leaving scores see app response florida argued hall found intellectually disabled florida law requires threshold matter hall show iq test score presenting additional evidence intellectual disability app nder law person mentally retarded florida rejected hall appeal held florida threshold constitutional granted certiorari ii eighth amendment provides xcessive bail shall required excessive fines imposed cruel unusual punishments inflicted fourteenth amendment applies restrictions roper simmons furman georgia per curiam protecting even convicted heinous crimes eighth amendment reaffirms duty government respect dignity persons roper supra see also trop dulles plurality opinion basic concept underlying eighth amendment nothing less dignity man eighth amendment fastened obsolete may acquire meaning public opinion becomes enlightened humane justice weems enforce constitution protection human dignity looks evolving standards decency mark progress maturing society trop supra eighth amendment protection dignity reflects nation nation nation aspire affirm nation constant unyielding purpose must transmit constitution precepts guarantees retain meaning force eighth amendment prohibits certain punishments categorical matter citizen may denaturalized ibid person may sentenced death crime committed juvenile roper supra relevant case persons intellectual disability may executed atkins legitimate penological purpose served executing person intellectual disability contravenes eighth amendment impose harshest punishments intellectually disabled person violates inherent dignity human unishment justified one three principal rationales rehabilitation deterrence retribution kennedy louisiana rehabilitation evident applicable rationale death penalty see gregg georgia joint opinion stewart powell stevens deterrence intellectual disability reason condition likely unable make calculated judgments premise deterrence rationale diminished ability process information learn experience engage logical reasoning control impulses make less likely process information possibility execution penalty result control conduct based upon information atkins retributive values also executing intellectual disability diminished capacity intellectually disabled lessens moral culpability hence retributive value punishment see culpability average murderer insufficient justify extreme sanction available state lesser culpability mentally retarded offender surely merit form retribution reason imposing death penalty person intellectually disabled protect integrity trial process persons face special risk wrongful execution likely give false confessions often poor witnesses less able give meaningful assistance counsel say current law persons intellectual disability meet law requirements criminal responsibility may tried punished may however receive law severe sentence question case presents intellectual disability must defined order implement principles holding atkins determine florida cutoff rule valid proper consider psychiatric professional studies elaborate purpose meaning iq scores determine scores relate holding atkins turn leads better understanding legislative policies various holdings state courts implement atkins rule understanding informs determination whether consensus instructs decide specific issue presented conclusion must express independent determination reached light instruction found sources authorities iii state courts state legislatures consult informed work medical experts determining intellectual disability unsurprising professionals use learning skills study consider consequences classification schemes devise diagnosis persons mental psychiatric disorders disabilities society relies upon medical professional expertise define explain diagnose mental condition issue definition intellectual disability skilled professionals implications far beyond confines death penalty relevant education access social programs medical treatment plans determining qualifies intellectually disabled proper consult medical community opinions noted atkins medical community defines intellectual disability according three criteria significantly subaverage intellectual functioning deficits adaptive functioning inability learn basic skills adjust behavior changing circumstances onset deficits developmental period see brief american psychological association et al amici curiae hereinafter apa brief last factor referred age onset issue first second criteria deficits intellectual functioning deficits adaptive functioning central context formal assessment existence concurrent deficits intellectual adaptive functioning long defining characteristic intellectual disability face florida statute consistent views medical community noted discussed atkins florida statute defines intellectual disability purposes atkins proceeding significantly subaverage general intellectual functioning existing concurrently deficits adaptive behavior manifested period conception age stat statute defines significantly subaverage general intellectual functioning performance two standard deviations mean score standardized intelligence test ibid mean iq test score concept standard deviation describes scores dispersed population standard deviation distinct standard error measurement concept describes reliability test discussed standard deviation iq test approximately points two standard deviations approximately points thus test taker performs two standard deviations mean score approximately points mean iq test score approximately points face statute interpreted consistently atkins conclusions reaches instant case nothing statute precludes florida taking account iq test standard error measurement discussed evidence florida legislature intended include measurement error calculation florida interpreted provisions held person whose test score including score within margin measurement error intellectual disability barred presenting evidence show faculties limited see cherry state per curiam strict iq test score cutoff issue case pursuant mandatory cutoff sentencing courts consider even substantial weighty evidence intellectual disability measured made manifest defendant failure inability adapt social cultural environment including medical histories behavioral records school tests reports testimony regarding past behavior family circumstances even though medical community accepts evidence probative intellectual disability including individuals iq test score see apa brief relevant clinical authorities agree individual iq score may properly diagnosed intellectual disability significant limitations adaptive functioning also exist person iq score may severe adaptive behavior problems person actual functioning comparable individuals lower iq score florida rule disregards established medical practice two interrelated ways takes iq score final conclusive evidence defendant intellectual capacity experts field consider evidence also relies purportedly scientific measurement defendant abilities iq score refusing recognize score terms imprecise professionals design administer interpret iq tests agreed years iq test scores read single fixed number range see wechsler measurement adult intelligence ed reporting range error early iq test iq test standard error measurement often referred abbreviation sem test sem statistical fact reflection inherent imprecision test see furr bacharach psychometrics ed identifying sem one important concepts measurement theory individual iq test score given exam may fluctuate variety reasons include health practice earlier tests environment location test examiner demeanor subjective judgment involved scoring certain questions exam simple lucky guessing see american association intellectual developmental disabilities schalock et user guide accompany edition intellectual disability definition classification systems supports hereinafter aaidd manual kaufman iq testing pp sem reflects reality individual intellectual functioning reduced single numerical score purposes iq tests sem means individual score best understood range scores either side recorded score sem allows clinicians calculate range within one may say individual true iq score lies see apa brief sem unit measurement sem equates confidence measured score falls within given score range sem provides confidence level measured score within broader range score instance generally considered reflect range confidence range confidence see individuals intellectual disability scores approximately two standard deviations population mean including margin measurement error generally points involves score apa brief example average sem iq test points average sem iq test points test manuals report sems different age groupings scores similar identical often due sampling error even person taken multiple tests separate score must assessed using sem analysis multiple iq scores jointly complicated endeavor see schneider principles assessment aptitude achievement oxford handbook child psychological assessment saklofske reynolds schwean eds addition test may flawed administered consistently flawed manner multiple examinations may result repeated similar scores even consistent score conclusive evidence intellectual functioning despite professional explanations florida law used test score fixed number thus barring consideration evidence bearing question intellectual disability professionals diagnose law determine whether intellectual disability exists sem applies individual iq score inquiry consider factors indicating whether person deficits adaptive functioning include evidence past performance environment upbringing significant majority implement protections atkins taking sem account thus acknowledging error inherent using test score without necessary adjustment calculation provides objective indicia society standards context eighth amendment roper kentucky virginia legislatures adopted fixed score cutoff identical florida rev stat ann lexis supp bowling commonwealth code ann lexis supp johnson commonwealth vacated remanded grounds alabama also may use strict iq score cutoff although result legislative action see smith state crim app alabama adopt error examining defendant iq score petitioner question rule use cutoff greater tr oral arg included alongside florida analysis addition arizona delaware kansas north carolina washington statutes interpreted provide cutoff leading result florida mandates cases see rev stat ann west del code ann tit supp stat ann supp stat ann lexis rev code state laws might interpreted require cutoff mean interpreted however see state vela neb although nebraska statute specifies intelligence quotient seventy reliably administered intelligence quotient test district found defendant score iq test considered light standard error measurement considered subaverage general intellectual functioning purposes diagnosing mental retardation arizona statute appears set broad statutory cutoff rev stat ann west another provision instructs courts take account margin error test administered id courts meant interpret statute situation like hall altogether clear principal arizona case matter state roque ariz statute accounts margin error requiring multiple tests defendant achieves score one tests proceeds hearing id case also notes defendant iq score well outside margin error one iq test id kansas execution almost five decades laws jurisprudence issue unlikely receive attention specific question see atkins ven allow execution mentally retarded offenders practice uncommon continue authorize executions none carried decades thus little need pursue legislation barring execution mentally retarded delaware executed three individuals past decade washington executed one person recently suspended death penalty none four individuals executed recently appears brought claim similar advanced thus nine mandate strict iq score cutoff four delaware kansas north carolina washington appear considered issue courts side ledger stand abolished death penalty either full new offenses oregon suspended death penalty executed two individuals past years see roper considered abandoned death penalty altogether part consensus juvenile death penalty course person hall position executed even without finding intellectual disability thus individual hall position individual iq score deemed automatically eligible death penalty aggregate numbers considerations bearing determination consensus consistency direction change also relevant see quoting atkins supra since atkins many passed legislation comply constitutional requirement persons intellectual disability executed two virginia delaware appear set strict cutoff although discussed delaware courts yet interpret law contrast least either abolished death penalty passed legislation allowing defendants present additional evidence intellectual disability iq test score since atkins five abolished death penalty legislation see pub acts comp stat ch west md correc servs code ann et seq lexis stat ann west supp laws ch addition new york appeals invalidated new york death penalty state constitution see people levalle legislation passed reinstate impose death penalty new york employ iq cutoff determining intellectual disability crim proc law ann west addition least five others passed legislation allowing defendant present additional evidence intellectual disability even iq test score see cal penal code ann west supp iq cutoff idaho code lexis supp seventy pizzutto state idaho alleged error iq testing plus minus five points district entitled draw reasonable inferences undisputed facts la code crim proc art west supp iq cutoff rev stat iq cutoff utah code ann lexis iq cutoff code likewise set strict iq cutoff see state previously allowed defendants iq score present additional evidence intellectual disability modified law create strict cutoff cf roper supra since stanford kentucky state previously prohibited capital punishment juveniles reinstated summary every state legislature considered issue atkins save virginia whose law interpreted courts taken position contrary florida indeed florida legislature passed relevant legislation prior atkins might well believed law create fixed cutoff staff analysis accompanying bill contain set iq level two standard deviations tests iq although extended senate staff analysis economic impact statement florida interpreted law require cutoff see cherry bound interpretation rejection strict cutoff vast majority consistency trend roper supra toward recognizing sem provide strong evidence consensus society regard strict cutoff proper humane atkins acknowledges inherent error iq testing true atkins provide definitive procedural substantive guides determining person claims mental retardation falls within protection eighth amendment bobby bies atkins stated people claim mentally retarded impaired fall within range mentally retarded offenders national consensus approach ford wainwright regard insanity leave state task developing appropriate ways enforce constitutional restriction upon execution sentences quoting ford wainwright citation omitted discussed play critical role advancing protections providing information contributes understanding intellectual disability measured assessed atkins give unfettered discretion define full scope constitutional protection atkins twice cited definitions intellectual disability express terms rejected strict iq test score cutoff atkins first cited definition provided mental retardation typically used describe people iq level approximately citing diagnostic statistical manual mental disorders ed later noted iq lower typically considered cutoff iq score intellectual function prong mental retardation definition furthermore immediately declared left task developing appropriate ways enforce constitutional restriction stated accompanying state statutory definitions mental retardation identical generally conform clinical definitions ibid thus atkins cited clinical definitions intellectual disability also noted standards based conclusion conformed definitions words atkins persons meet clinical definitions intellectual disability definition diminished capacities understand process information communicate abstract mistakes learn experience engage logical reasoning control impulses understand reactions others thus bear diminish ed personal culpability ibid clinical definitions intellectual disability take account iq scores represent range fixed number fundamental premise atkins clinical definitions long included sem see diagnostic statistical manual mental disorders rev ed since measurement fallible iq score generally thought involve error measurement approximately five points hence iq considered represent band zone treating iq flexibility permits inclusion mental retardation category people iqs somewhat higher exhibit significant deficits adaptive behavior respondent argues current florida law favorably cited atkins see brief respondent evidence national consensus specifically cited florida statute issue substantively changed atkins refer florida law citation listing outlawed execution intellectually disabled fleeting mention signal approval florida current understanding law discussed atkins decided florida yet interpreted law require strict iq cutoff new interpretation runs counter clinical definition cited throughout atkins florida legislative report indicating kind cutoff need used respondent argument also conflicts logic atkins eighth amendment complete autonomy define intellectual disability wished decision atkins become nullity eighth amendment protection human dignity become reality thus reads atkins provide substantial guidance definition intellectual disability actions precedents give us essential instruction roper inquiry must go constitution contemplates end judgment brought bear question acceptability death penalty eighth amendment coker georgia plurality opinion exercise independent judgment judicial duty see roper supra extent stanford based rejection idea required bring independent judgment bear proportionality death penalty particular class crimes offenders suffices note rejection inconsistent prior eighth amendment decisions citation omitted independent judgment florida statute interpreted courts unconstitutional addition views precedent determination informed views medical experts views dictate decision yet disregard informed assessments see kansas crane science psychiatry informs control ultimate legal determinations duty interpret constitution need isolation legal determination intellectual disability distinct medical diagnosis informed medical community diagnostic framework atkins points diagnostic criteria employed psychiatric professionals professional community teachings particular help case alternative definition intellectual disability presented placed substantial reliance expertise medical profession failing take account sem setting strict cutoff florida goes unanimous professional consensus apa brief neither florida amici point single medical professional supports cutoff repudiates iq test scores approximations conceptual functioning may insufficient assess reasoning situations mastery practical tasks statement well captures independent assessment individual iq test score lower atkins supra may show intellectual disability presenting additional evidence regarding difficulties adaptive functioning flaws florida law result inherent error iq tests iq score approximation final infallible assessment intellectual functioning see apa brief standard pyschometric practice report relevant reliabilities standard errors measurement reporting test score ibid margin error inherent accuracy iq scores furr psychometrics standard error measurement important psychometric value implications applied measurement sem concept peculiar psychiatric profession iq tests measure recognized relied upon create devise tests sorts identifying sem one important concepts measurement theory awareness iq test limits particular importance conducting conjunctive assessment necessary assess individual intellectual ability see american association intellectual developmental disabilities intellectual disability definition classification systems supports ed must stressed diagnosis intellectual disability intended reflect clinical judgment rather actuarial determination intellectual disability condition number see courts must recognize medical community iq test imprecise say iq test score unhelpful considerable significance medical community recognizes using scores assess defendant eligibility death penalty state must afford test scores studied skepticism design use tests understand iq test score represents range rather fixed number state ignores inherent imprecision tests risks executing person suffers intellectual disability see apa brief universally accepted clinical standards diagnosing intellectual disability determination hall intellectually disabled considered valid agrees medical experts defendant iq test score falls within test acknowledged inherent margin error defendant must able present additional evidence intellectual disability including testimony regarding adaptive deficits sound view single factor dispositive conjunctive interrelated assessment see person iq score may severe adaptive behavior problems person actual functioning comparable individuals lower iq score florida statute interpreted courts misuses iq score terms turn bars consideration evidence must considered determining whether defendant capital case intellectual disability florida rule invalid constitution cruel unusual punishments clause florida seeks execute man scored instead iq test florida one rigid rule florida rule misconstrues statements atkins intellectually characterized iq approximately florida rule direct opposition views design administer interpret iq test failing take account standard error measurement florida law contradicts test design also bars essential part sentencing inquiry adaptive functioning freddie lee hall may may intellectually law requires opportunity present evidence intellectual disability including deficits adaptive functioning lifetime death penalty gravest sentence society may impose persons facing severe sanction must fair opportunity show constitution prohibits execution florida law contravenes nation commitment dignity duty teach human decency mark civilized world laboratories experimentation experiments may deny basic dignity constitution protects judgment florida reversed case remanded proceedings inconsistent opinion ordered alito dissenting freddie lee hall petitioner florida writ certiorari florida may justice alito chief justice justice scalia justice thomas join dissenting atkins virginia held eighth amendment prohibits death sentence defendants intellectually disabled mandate use single method identifying defendants today overrules latter holding based largely positions adopted private professional associations taking step sharply departs framework prescribed prior eighth amendment cases adopts uniform national rule conceptually unsound likely result confusion therefore respectfully dissent approach case marks new unwise turn eighth amendment case law atkins cases held prohibition cruel unusual punishment embodies evolving standards decency mark progress maturing society explained evolving standards informed objective factors maximum possible extent internal quotation marks omitted addition pinpointed clearest reliable objective evidence contemporary values legislation enacted country legislatures ibid prior cases referred evolving standards maturing society meant standards american society whole however strikes state law based evolving standards professional societies notably american psychiatric association apa begins analysis views associations see ante briefly discussing enactments state legislatures see ante returns associations views interpreting atkins exercising independent judgment constitutionality florida law see ante approach reconciled framework prescribed eighth amendment cases modern eighth amendment precedents whether punishment cruel unusual depends currently prevailing societal norms long held laws enacted state legislatures provide clearest reliable objective evidence contemporary values penry lynaugh democratic society legislatures courts constituted respond consequently moral values people gregg georgia joint opinion stewart powell stevens jj internal quotation marks omitted approach originally conceived first asked whether challenged practice contravened clear national consensus evidenced state legislation consensus found go ask whether reason disagree judgment atkins invoking procedure atkins held eighth amendment forbids execution defendants intellectually disabled see critical analysis conclusion today society views mentally retarded offenders categorically less culpable average criminal consensus continued unquestionably reflects widespread judgment relationship mental retardation penological purposes served death penalty atkins identified consensus execution intellectually disabled observed serious disagreement among respect best method determining offenders fact retarded ibid therefore le ft task developing appropriate ways identify defendants ibid internal quotation marks alteration omitted noted five years ago atkins provide definitive procedural substantive guides determining person intellectually disabled bobby bies consistent role atkins left florida follows procedure issue explained atkins order defendant qualify intellectually disabled three separate requirements must met must shown defendant significantly subaverage intellectual functioning deficits adaptive behavior onset factors occurred age see ante implementing framework determined first requirement satisfied defendant scores higher iq tests method measuring intellectual today holds scheme offends eighth amendment objects florida approach treats iq test scores conclusive ignores fact iq score might reflect true iq errors measurement concludes state must view defendant iq range potential scores calculated using statistical concept known standard error measurement sem see part infra holds range includes iq accepted level intellectual disability defendant must permitted produce evidence intellectual disability addition iq scores see support holding traditional approach identifying society evolving standards decency fair analysis current state laws absence consensus found atkins persists today telling hall rely consensus among candidly argues instead precise number share florida approach immaterial reply brief analysis aggressive according significant majority reject florida strict cutoff instead take sem account deciding whether defendant meets first requirement test ante count nine mandate strict iq score cutoff allow defendants present additional evidence individual test score ante abolished death penalty long suspended operation ante numbers concludes defendant iq score deemed automatically eligible death penalty analysis deeply flawed begin addition recognizes rules similar florida idaho appear require courts take sem account rejecting claim intellectual remaining death penalty either said nothing sem clarified whether require accordingly including florida require sem taken account consider sem taken definitive position question statistics regarded establishing national consensus florida approach attempting circumvent statistics includes count never impose death penalty maneuver justified true counted prior eighth amendment cases cases concerned substantive question whether class individuals categorically ineligible death penalty roper simmons example counted part consensus imposition capital sentence crime committed minor reasoned state decision abolish death penalty necessarily demonstrates judgment death penalty inappropriate offenders including juveniles ibid similar reasoning possible fact state abolished death penalty says nothing state resolve evidentiary problem identifying defendants intellectually disabled explain state may reasonably conclude florida approach fairer accurate approach requires therefore inferred state forced choose two approaches necessarily select reasons quite wrong proclaim vast majority rejected florida approach ante divided question whether sem play role determining whether capital defendant intellectually disabled require consideration sem agree role sem play differ example sort evidence introduced iq testing reveals iq require evidence intellectual deficits others permit defendant move second prong test submit evidence deficits adaptive fairest assessment current situation adopted multitude approaches difficult question light resolution case straightforward methodological consensus among time atkins consensus today absence consensus basis holding florida method contravenes society standards decency perhaps recognizes weakness arguments true national consensus places heavy reliance views recently announced professional organizations attempts downplay degree decision dependent upon views private groups game attempt shoehorn views associations calculus reasons follows views associations help determining iq scores relate holding atkins turn leads better understanding legislative policies various holdings state courts implement atkins rule hat understanding informs determination whether consensus instructs decide specific issue presented ante follow logic modern eighth amendment cases counts society standards say standards american people standards professional associations best represent views small professional elite also mistakenly suggests dictated atkins see ante contrary atkins expressly left task defining intellectual disability although atkins perceived professional consensus best procedure used identifying intellectually atkins declined import view law instead made clear professional consensus means dispositive see reliance views professional associations also lead serious practical problems briefly note first views professional associations often tying eighth amendment law views lead instability continue fuel litigation danger dramatically illustrated recent publication apa relies publication fundamentally alters first prong longstanding definition intellectual disability embraced atkins adopted new publication apa discards significantly subaverage intellectual functioning element elevating apa current views constitutional significance therefore throws question basic approach atkins approved followed also noteworthy changes adopted professional associations sometimes rescinded example aaidd extended baseline intellectual functioning cutoff iq score approximately aaidd ed table boldface deleted see kaplan sadock comprehensive textbook psychiatry sadock sadock ruiz ed hereinafter kaplan sadock change generated much controversy used aaidd definition continuing use definition ibid aaidd baseline iq changed back approximately less ibid second approach implicitly calls upon judiciary either follow every new change thinking professional organizations judge validity new change example tacitly makes judgment diagnostic criteria intellectual disability prevailed time atkins decided longer legitimate publications atkins cited differ markedly recent editions endorsed see third approach requires judiciary determine professional organizations entitled special deference professional organizations disagree provides guidance deciding organizations views govern fourth binds eighth amendment law definitions intellectual disability promulgated use making variety decisions quite different decision whether imposition death sentence particular case serve valid penological end case intellectual functioning important correlation ability understand gravity crime purpose penalty well ability resist momentary impulse influence others see contrast determining eligibility social services adaptive functioning may much important cf xxxvii clinical considerations may relevant legal judgments turn individual responsibility similar practical problems like call legislative judgments judicial resolution ii find consensus among independently assess method florida adopted determining intellectual disability even appropriate us look beyond evidence societal standards conclude florida method unconstitutional faults florida tak ing iq score final conclusive evidence defendant intellectual capacity failing recognize iq score may imprecise ante view however florida adopted sensible standard comports longstanding belief iq tests best measure intellectual functioning although entirely ignores part florida scheme state takes account inevitable risk testing error permitting defendants introduce multiple scores contrast establishes standard conflates long understood two independent requirements proving intellectual disability significantly subaverage intellectual functioning deficits adaptive behavior also mandates use alternative method dealing risk testing error without hint accurate florida approach first supposed error identifies florida takes iq score conclusive evidence intellectual functioning ante initial matter one get impression reading opinion hall introduced one test score see ante truth florida courts considered multiple scores particular iq test hall dubbed gold standard see brief petitioner app florida statute imposes limit number iq scores defendant may introduce simply wrong analyze florida system one views single iq score final conclusive evidence defendant suffer subaverage intellectual functioning see brief respondent florida rule allows multiple evaluations hall believed statistical error rate prevented tests reflecting true score sought still testing proper question ask therefore whether actual approach falls outside range discretion allowed atkins offers persuasive reason concluding indeed opinion never identifies evidence intellectual functioning require florida admit recognized atkins longstanding practices least previous views professional organizations seem reflect understanding iq scores best way measure intellectual functioning see recent publication apa example ranked severity intellectual disability exclusively iq scores necessarily pinpointing onset disability according iq see presented solid evidence longstanding reliance multiple iq test scores measure intellectual functioning unreasonable outside ordinary unconstitutional certainly supplied information merely held florida must permit defendants introduce additional evidence whatever might significantly subaverage intellectual functioning decision limited scope understand opinion also holds iq tests reveal iq defendants must allowed present evidence deficits adaptive behavior second prong test see ante remarkable change took universal understanding intellectual disability years ago atkins instructed clinical definitions mental retardation require subaverage intellectual functioning also significant limitations adaptive skills emphasis alterations added approach taken vast majority correctly recognizes require concurrent deficits intellectual functioning adaptive behavior requiring defendants prove ante emphasis added yet holds defendant iq score high must consider factors indicating whether person deficits adaptive functioning ante see ante words even defendant failed show meets first prong standard intellectual disability significantly subaverage functioning evidence second prong deficits adaptive behavior establish intellectual disability offers little explanation sea change asserts vaguely sound view single factor dispositive conjunctive interrelated assessment ante ignores fact deficits adaptive behavior used establish deficits mental functioning two prongs meant show distinct components intellectual disability ntellectual functions include reasoning problem solving planning abstract thinking judgment academic learning learning experience adaptive functioning refers ability meet developmental sociocultural standards personal independence social responsibility strong evidence deficit adaptive behavior necessarily demonstrate deficit intellectual functioning without latter person simply classified intellectually disabled particularly troubling relax proof requirements prong prong directly relates concerns led primary holding atkins explained diminished ability understand process information learn experience engage logical reasoning control impulses diminished intellectual functioning make less likely defendant process information possibility execution penalty therefore deterred committing murders see also hey often act impulse rather pursuant premeditated plan see also ante defendant display significantly subaverage intellectual functioning therefore among class defendants identified atkins finally relying primarily proof adaptive deficits produce inequities administration capital punishment far tell adaptive behavior malleable factor without firm theoretical empirical roots see kaplan sadock consensus exists among medical practitioners facts critical analyzing factor measurement relies largely subjective judgments florida approach avoids disparities reliance factor tends produce thus promotes consistency application death penalty confidence administered haphazardly second interrelated objection florida rule fails account risk error inherent iq testing order diminish risk establishes rule iq testing reveals iq claim intellectual disability rejected basis test scores alone ante misunderstands sem works fails explain florida method accounting risk error allowing defendant take rely multiple tests effective approach compels begins simple uncontroversial proposition every testing situation susceptible error thus may result imperfect measurement true iq wades technical matters must understood order see goes wrong various ways account error iq testing one way florida approach evaluate multiple test results another use mathematical measurement called standard error measurement sem see aamr ed app critical importance single uniform sem across iq tests even across rather sem varies test subgroup age group user guide accompany aaidd ed definition classification systems supports know sem particular test particular adding one sem subtracting one sem obtained score establishes interval scores known confidence interval see aamr ed interval represents range scores within sure true iq falls see oxford handbook child psychological assessment saklofske reynolds schwean eds interval centered obtained score includes scores score amount sem since chance true iq falls within range chance true iq falls outside interval approximately equal odds falls interval interval example scores iq test sem confidence interval range situation approximately chance true iq roughly chance roughly chance thus chance score similarly using two sems build confidence interval process except add two sems subtract two sems obtained score illustrate use two sems let us hypothesize case defendant obtained score sem prior example chance true score roughly chance score chance score probability true score roughly two examples show greater degree confidence demanded greater range scores fall within confidence interval therefore away obtained score yet still fall within confidence interval misunderstands principles makes factual mistakes surely confuse attempting comply opinion first unjustifiably assumes blanket common error measurement see ante assumption gives rise holding defendant must permitted introduce additional evidence iq tests reveal iq high see ibid sems however vary iq test reason assume sem points indeed appears sem generally estimated three five points iq tests aamr ed know sem hall recent iq test less half estimate brief petitioner relatedly misreads authorities relies establish cutoff iq score true certain professional organizations advocated cutoff atkins cited organizations cutoff see ante overlooks critical fact organizations endorsed iq cutoff based express understanding one standard error measurement sem three five points iq tests aamr mental retardation ed hereinafter aamr ed atkins citing aamr ed kaplan sadock sadock sadock ed see also aamr ed aaidd ed words number relevant extent single sem estimated high points aamr ed contrast know sem hall latest iq test less half estimate relevance number case blindly import margin error know matter fact relevant sem amounts requiring consideration two sems approach finds support atkins anywhere else factual errors ambiguities unclear whether concludes defendant constitutionally entitled introduce evidence intellectual disability whenever score lower mistaken understanding sem tests confidence interval using one sem includes score confidence interval using two sems includes score view none approaches defensible approach tied fixed score dismissed hand discussed every test different sem two approaches require defendant permitted submit additional evidence iq long confidence interval using one sem two sems respectively includes score foundation eighth amendment case law hall concedes eighth amendment permits assign defendant burden establishing intellectual disability least preponderance evidence see tr oral arg words defendant required prove probability iq greater approach contrast defendant prove significantly subaverage intellectual functioning showing simply probability true iq little rule rule totally transforms allocation nature burden proof referred confidence intervals result straightforward application sem context one sem establishes confidence interval two sems establish confidence interval see aaidd ed simple enough devise confidence interval confidence interval matter therefore excuse mechanically imposing standards unhinged legal logic override valid state laws establishing burdens proof appropriate confidence level ultimately judgment best left legislatures judgment defendant must establish likely intellectually disabled defer determination also fails grasp florida system already accounts risk testing error allowing introduction multiple test scores never explains criticisms uncertainty resulting use single iq score apply defendant consistently scores multiple tests contrary evident assumption view multiple consistent scores establish much higher degree attempt address say analysis multiple iq scores jointly complicated endeavor ante evaluation intellectual disability whether based objective tests subjective observations complicated conducting proper analysis multiple scores produces iq reliable approach mandated basis rejecting florida reasons affirm judgment florida footnotes see american association intellectual developmental disabilities aaidd intellectual disability ed hereinafter aaidd ed cataloguing history iq cutoff criteria since earlier publications aaidd published former name american association mental retardation hereinafter aamr assume additional evidence means evidence iq testing florida rule already allows multiple evaluations petitioner sought still testing brief respondent see also brief petitioner app discuss florida base decision finding hall iq florida courts considered several iq scores see app brief petitioner see idaho code lexis cum supp pizzuto state idaho stating legislature require iq score within five points giving district discretion interpret defendant iq montana new hampshire wyoming ruled subject two defined significantly subaverage intellectual functioning see rev stat ann code ann cum supp franklin maynard per curiam two statutes impose rebuttable presumptions intellectual disability defendant iq said whether defendant allowed provide evidence iq see ark code ann neb rev stat one state mentioned measurement errors explain defendant must prove deficits adaptive behavior despite iq see stripling state another state mentioned sem responding argument defendant suggest sem legally relevant see goodwin state mo compare ybarra state state dunn pp la see forensic psychology neuropsychology criminal civil cases hall ed hereinafter forensic psychology compare apa diagnostic statistical manual mental disorders rev ed hereinafter apa diagnostic statistical manual mental disorders ed hereinafter see brief petitioner listing valid iq scores hall alleges also scored wechsler test score admitted evidence doubts validity app hall allege potential practice effect skewed scores see aaidd ed cataloguing history iq cutoff criteria since mental retardation characterized significantly subaverage intellectual functioning iq approximately boldface deleted general intellectual functioning defined intelligence quotient italics deleted aamr mental retardation ed hereinafter aamr ed ntellectual functioning still best represented iq scores see del code tit idaho code rev stat code ann lexis cum supp longstanding views professional organizations also intellectual functioning adaptive behavior independent factors see organizations might recommend examining evidence adaptive behavior even iq sheds light legal rule given appear require defendants prove prong separately preponderance evidence see oxford handbook child psychological assessment saklofske reynolds schwean eds multiple scores provide greater precision frances essentials psychiatric diagnosis responding challenge rev ed pattern test scores important score given test multiple scores moreover good reason treat low scores differently high scores although one better iq test one capable one certainly worse forensic psychology sharp unexplained drop iq scores following incarceration strong evidence malingering frances supra igher scores likely indicative since many reasons given score might underestimate person intelligence reason scores overestimate also iq testing may flawed multiple examinations may result repeated similar scores conclusive evidence intellectual functioning ante argument proves much potential flaws administering multiple tests sufficient render inaccurate conclude even scores sufficient appropriate remedy incorrectly administered tests disregard tests ignore fact multiple properly administered tests yielding scores give high degree confidence individual intellectually disabled