taylor illinois argued october decided january well advance petitioner trial attempted murder prosecutor filed discovery motion requesting list defense witnesses petitioner answer failed list one wormley amended answer submitted accepted first day trial identifying two witnesses never called testify second day trial prosecution two principal witnesses completed testimony petitioner counsel made oral motion amend discovery answer include wormley counsel explained wormley probably seen entire incident led indictment although petitioner told counsel wormley earlier counsel unable locate wormley subsequent voir dire examination wormley testified witness incident earlier seen victim brother carrying guns threatening petitioner happened run petitioner warned watch wormley acknowledged first met petitioner two years incident question defense counsel visited home week trial began sanction failure identify wormley discovery answer trial judge refused allow wormley testify jury judge explained petitioner counsel committed blatant willful violation discovery rules judge doubted veracity wormley testimony illinois appellate affirmed petitioner conviction held compulsory process clause sixth amendment may appropriate case violated imposition discovery sanction entirely excludes testimony material defense witness clause merely guarantee accused shall power subpoena witnesses confers accused fundamental right present witnesses defense pp however compulsory process clause create absolute bar preclusion testimony defense witness sanction violating discovery rule although trial may ignore fundamental character defendant right offer testimony witnesses favor mere invocation right automatically invariably outweigh countervailing public interests discovery violations willful motivated desire obtain tactical advantage conceal plan present fabricated testimony entirely appropriate exclude witnesses testimony regardless whether less drastic sanctions might available adequate merited pp exclusion wormley testimony constitute constitutional error pp fact voir dire examination wormley may adequately protected prosecution prejudice resulting surprise render imposition preclusion sanction unnecessarily harsh record raises strong inferences petitioner counsel deliberately seeking tactical advantage failing list wormley witness witnesses found really thus case fits category willful misconduct severe sanction preclusion justified order protect integrity judicial process pp unfair hold petitioner responsible lawyer misconduct lawyer necessarily full authority manage conduct trial client must accept consequences lawyer trial decisions pp stevens delivered opinion rehnquist white scalia joined brennan filed dissenting opinion marshall blackmun joined post blackmun filed dissenting opinion post richard cunningham argued cause petitioner briefs paul biebel robert isaacson emily eisner michael shabat argued cause respondent brief neil hartigan attorney general illinois jill deputy attorney general roma stewart solicitor general joan fickinger assistant attorney general solicitor general fried assistant attorney general weld deputy solicitor general bryson paul larkin sidney glazer filed brief amicus curiae urging affirmance justice stevens delivered opinion sanction failing identify defense witness response pretrial discovery request illinois trial judge refused allow undisclosed witness testify question presented whether refusal violated petitioner constitutional right obtain testimony favorable witnesses hold sanction absolutely prohibited compulsory process clause sixth amendment find constitutional error specific facts case jury convicted petitioner attempting murder jack bridges street fight south side chicago august conviction supported testimony bridges brother three witnesses described argument bridges young man named derrick travis violent encounter occurred hour later several friends travis including petitioner one hand bridges belatedly aided brother incident witnessed bystanders undisputed least three members group included travis petitioner carrying pipes clubs used beat bridges prosecution witnesses also testified petitioner gun shot bridges back attempted flee bridges fell petitioner pointed gun bridges head weapon misfired two sisters friends petitioner testified behalf many respects version incident consistent prosecution case testified bridges brother rather petitioner possessed firearm fired group hitting brother mistake witnesses testified defense well advance trial prosecutor filed discovery motion requesting list defense witnesses original response petitioner attorney identified two sisters later testified two men testify first day trial defense counsel allowed amend answer adding names derrick travis chicago police officer neither actually testified second day trial prosecution two principal witnesses completed testimony defense counsel made oral motion amend answer discovery include two witnesses alfred wormley pam berkhalter support motion counsel represented informed probably seen entire incident response inquiry defendant failure tell two witnesses earlier counsel acknowledged defendant done represented unable locate wormley noting witnesses names supplied even addresses unknown trial judge directed counsel bring next day time decide whether testify judge indicated concerned possibility witnesses found really next morning wormley appeared defense counsel colloquy consequences violation discovery rules counsel permitted make offer proof form wormley testimony outside presence jury developed wormley witness incident testified prior incident saw jack bridges brother two guns blanket heard say ray petitioner people way home happened run ray warned watch got weapons wormley acknowledged first met defendant four months ago two years incident also acknowledged defense counsel visited home wednesday week trial began thus testimony rather dramatically contradicted defense counsel representations trial hearing wormley testify trial judge concluded appropriate sanction discovery violation exclude testimony judge explained right going deny wormley opportunity testify going testify find blatent sic violation discovery rules willful violation rules also feel defense attorneys violating discovery courtroom last three four cases blatantly going put stop one way whatever value jury trial great deal doubt mind veracity young man testified whether eyewitness scene sees guns wrapped know ray stops ray rate wormley going testify witness courtroom app petitioner makes two arguments first contends sixth amendment bars ever ordering preclusion defense evidence sanction violating discovery rule alternatively contends even right present witnesses absolute facts case preclusion wormley testimony constitutional error addressing contentions consider state argument compulsory process clause sixth amendment merely guarantee accused shall power subpoena witnesses simply apply rulings admissibility evidence ii state view compulsory process clause concerns even raised authorizing preclusion discovery sanction application illinois rule case state argument supported plain language clause see supra historical evidence intended provide defendants subpoena power lacked common law scholarly comment brief excerpt legislative history clause however consistently given clause broader reading reflected contemporaneous state constitutional provisions noted last term ur cases establish minimum criminal defendants right government assistance compelling attendance favorable witnesses trial right put jury evidence might influence determination guilt pennsylvania ritchie rights fundamental accused present witnesses defense see chambers mississippi indeed right essential attribute adversary system elected employ adversary system criminal justice parties contest issues law need develop relevant facts adversary system fundamental comprehensive ends criminal justice defeated judgments founded partial speculative presentation facts integrity judicial system public confidence system depend full disclosure facts within framework rules evidence ensure justice done imperative function courts compulsory process available production evidence needed either prosecution defense nixon right offer testimony witnesses compel attendance necessary plain terms right present defense right present defendant version facts well prosecution jury may decide truth lies accused right confront prosecution witnesses purpose challenging testimony right present witnesses establish defense right fundamental element due process law washington texas iii petitioner claim sixth amendment creates absolute bar preclusion testimony surprise witness extreme unacceptable state position amendment simply irrelevant accused unfettered right offer testimony incompetent privileged otherwise inadmissible standard rules evidence compulsory process clause provides effective weapon weapon used irresponsibly significant difference compulsory process clause weapon rights protected sixth amendment availability dependent entirely defendant initiative sixth amendment rights arise automatically initiation adversary process action defendant necessary make active case rights shield defendant potential prosecutorial abuses right compel presence present testimony witnesses provides defendant sword may employed rebut prosecution case decision whether employ particular case rests solely defendant nature right requires effective use preceded deliberate planning affirmative conduct principle undergirds defendant right present exculpatory evidence also source essential limitations right adversary process function effectively without adherence rules procedure govern orderly presentation facts arguments provide party fair opportunity assemble submit evidence contradict explain opponent case trial process shambles either party absolute right control time content witnesses testimony neither may insist right interrupt opposing party case obviously absolute right interrupt deliberations jury present newly discovered evidence state interest orderly conduct criminal trial sufficient justify imposition enforcement firm though always inflexible rules relating identification presentation evidence defendant right compulsory process designed vindicate principle ends criminal justice defeated judgments founded partial speculative presentation facts nixon rules provide pretrial discovery opponent witnesses serve high purpose discovery like minimizes risk judgment predicated incomplete misleading even deliberately fabricated testimony state interest protecting defense merely one component broader public interest full truthful disclosure critical facts vindicate interest held even defendant may testify without subjected brown moreover nobles upheld order excluding testimony expert witness tendered defendant refused permit discovery highly relevant report writing justice powell explained preclusion sanction entirely proper method assuring compliance order respondent argument ruling deprived sixth amendment rights compulsory process misconceives issue district bar investigator testimony cf washington texas merely prevented respondent presenting jury partial view credibility issue adducing investigator testimony thereafter refusing disclose contemporaneous report might offer critical insights sixth amendment confer right present testimony free legitimate demands adversarial system one invoke sixth amendment justification presenting might deciding within discretion assure jury hear full testimony investigator rather truncated portion favorable respondent think artificial indeed deprive power effectuate judgment find constitutional significance fact instance able exclude testimony advance rather receive evidence thereafter charge jury disregard respondent counsel refused said produce report emphasis added may well true alternative sanctions adequate appropriate cases equally clear less effective preclusion sanction instances perpetuate rather limit prejudice state harm adversary process one purposes discovery rule minimize risk fabricated testimony believed defendants willing fabricate defense may also willing fabricate excuses failing comply discovery requirement risk contempt violation may seem trivial defendant facing threat imprisonment term years dishonest client mislead honest attorney occasions attorney assumes duty loyalty client outweighs elementary obligations presume evidence discovered trial affected outcome equally reasonable presume something suspect defense witness identified hour passed pattern discovery violations explicable assumption violations designed conceal plan present fabricated testimony entirely appropriate exclude tainted evidence regardless whether sanctions also merited order reject petitioner argument preclusion never permissible sanction discovery violation neither necessary appropriate us attempt draft comprehensive set standards guide exercise discretion every possible case elementary course trial may ignore fundamental character defendant right offer testimony witnesses favor mere invocation right automatically invariably outweigh countervailing public interests integrity adversary process depends presentation reliable evidence rejection unreliable evidence interest fair efficient administration justice potential prejudice function trial process must also weigh balance trial judge may certainly insist explanation party failure comply request identify witnesses advance trial explanation reveals omission willful motivated desire obtain tactical advantage minimize effectiveness ability adduce rebuttal evidence entirely consistent purposes compulsory process clause simply exclude witness testimony cf nobles simplicity compliance discovery rule also relevant noted compulsory process clause invoked without prior planning affirmative conduct defendant lawyers accustomed meeting deadlines routine preparation involves location interrogation potential witnesses serving subpoenas whose testimony offered trial burden identifying advance trial adds little routine demands trial preparation demean high purpose compulsory process clause construe encompassing absolute right automatic continuance mistrial allow presumptively perjured testimony presented jury reject petitioner argument preclusion sanction never appropriate matter serious defendant discovery violation may iv petitioner argues preclusion sanction unnecessarily harsh case voir dire examination wormley adequately protected prosecution possible prejudice resulting surprise petitioner also contends unfair visit sins lawyer upon client neither argument merit stake possible prejudice prosecution also concerned impact kind conduct integrity judicial process trial judge found discovery violation case willful blatant view fact petitioner counsel actually interviewed wormley week trial began fact amended answer discovery first day trial without identifying wormley identify two actual eyewitnesses place stand inference deliberately seeking tactical advantage inescapable regardless whether prejudice prosecution avoided particular case plain case fits category willful misconduct severest sanction appropriate well prosecutor vital interest protecting trial process pollution perjured testimony evidentiary rules apply categories inadmissible evidence ranging hearsay fruits illegal searches may properly enforced even though particular testimony offered prejudicial pretrial conduct revealed record case gives rise sufficiently strong inference witnesses found really justify sanction preclusion argument client held responsible lawyer misconduct strikes heart relationship although basic rights attorney waive without fully informed publicly acknowledged consent client lawyer must full authority manage conduct trial adversary process function effectively every tactical decision required client approval moreover given protections afforded privilege fact extreme cases may involve unscrupulous conduct client lawyer highly impracticable require investigation relative responsibilities applying sanction preclusion responding discovery client duty candid forthcoming lawyer lawyer responds speaks client putting one side exceptional cases counsel ineffective client must accept consequences lawyer decision forgo decide put certain witnesses stand decide disclose identity certain witnesses advance trial case petitioner greater right disavow lawyer decision conceal wormley identity trial commenced disavow decision refrain adducing testimony eyewitnesses identified answer discovery whenever lawyer makes use sword provided compulsory process clause risk may wound client judgment illinois appellate affirmed footnotes illinois rule provides pertinent part subject constitutional limitations within reasonable time filing written motion state defense counsel shall inform state defenses intends make hearing trial shall furnish state following material information within possession control names last known addresses persons intends call witnesses together relevant written recorded statements including memoranda reporting summarizing oral statements record prior criminal convictions known emphasis added two men earl travis brother derrick travis luther taylor petitioner brother identified prosecution witnesses participants street fight direct testimony witnesses honor called state informed additional witnesses probably fact see entire incident time ask amend answer include two additional witnesses van one guy named alfred wrdely defendant excuse van whose address going see locate tonight pam berkhalter app yeah defendant defendant telling pam berkhalter telling alfred wrdely tell sometime ago got obligation tell van correct judge fact told alfred sometime ago problem locate alfred sorts people scene people disclosed bring witnesses last moment always allegation thought process witnesses found really problem types cases put sheet long time ago rate worry tomorrow record explain pam berkhalter appear anything learn standing crowd well jack blanket two pistols gave anything say time recall well saying going people say ray people anything time time left way home happened run ray told happening watch got weapons state also argues decline exercise jurisdiction petitioner sixth amendment claim inadequately presented state respondent points petitioner specifically articulate claim based compulsory process clause filed petition rehearing illinois appellate moreover trial petitioner merely argued trial erred letting witness testify appeal however petitioner asserted error constitutional trial judge abused discretion denied petitioner due process excluding material defense witness testifying sanction discovery violation brief argument appellant app although petitioner expressly asserted due process violation reliance sixth amendment clear cited relied upon quotation illinois appellate decision two compulsory process clause cases washington texas chambers mississippi decision petitioner quoted people rayford app also compulsory process clause case rayford asserted use preclusion sanction criminal cases limited extreme situations criminal cases due process requires defendant permitted offer testimony witnesses defense emphasis added citing washington supra generic reference fourteenth amendment sufficient preserve constitutional claim based unidentified provision bill rights case authority cited petitioner manner fundamental right issue described understood illinois courts make appropriate conclude constitutional question sufficiently well presented state courts support jurisdiction see clinton right present defense emergent constitutional guarantee criminal trials ind rev wigmore evidence pp mcnaughton rev burke moved amend proposition manner leave power accused put trial next session provided made appear evidence witnesses process granted served material defence hartley said securing right compulsory process government remainder must lie discretion smith south carolina thought regulation come properly part judicial system question burke motion taken lost ayes noes annals cong particulars varied state state provisions reflected common principle three emphasized right present evidence guaranteeing accused right call evidence favour two emphasized subpoena power giving defendant right produce proofs may favorable north carolina combined right put defense right confrontation guaranteeing right confront accusers witnesses testimony delaware emphasized defendant interest sworn testimony giving right examine evidence oath favour new jersey opted principle equality parties criminals shall admitted privileges witnesses counsel prosecutors shall entitled maryland consolidated several interests guaranteeing defendant right examine witnesses oath process witnesses state provisions originated english statutes colonial enactments original regardless reflected principle defendant must meaningful opportunity least advantageous possessed prosecution establish essential elements case pressed principle vigorously framers federal bill rights included sixth amendment distinctive formulation westen compulsory process clause rev footnotes omitted one commentator noted defendant rights informed charges receive speedy public trial tried jury assisted counsel confronted adverse witnesses designed restrain prosecution regulating procedures presents case accused apply every case whether defendant seeks rebut case present case compulsory process hand comes play close prosecution case operates exclusively defendant initiative provides affirmative aid presenting defense exercise right present witnesses accused required state must comply established rules procedure evidence designed assure fairness reliability ascertainment guilt innocence chambers mississippi rules use large growing number based proposition ends justice best served system liberal discovery gives parties maximum possible amount information prepare cases thereby reduces possibility surprise trial see brennan criminal prosecution sporting event quest truth american bar association project standards criminal justice discovery procedure trial approved draft goldstein state accused balance advantage criminal procedure yale growth discovery devices salutary development increasing evidence available parties enhances fairness adversary system wardius oregon given ease alibi fabricated state interest protecting defense obvious legitimate reflecting interest provisions dating least existence substantial number adversary system trial hardly end yet poker game players enjoy absolute right always conceal cards played find ample room system least far due process concerned instant florida rule designed enhance search truth criminal trial insuring defendant state ample opportunity investigate certain facts crucial determination guilt innocence williams florida footnotes omitted lloyd gill motion new trial based newly discovered evidence may granted unless facts discovered nature probably change result new trial granted discovered since trial exercise due diligence discovered earlier merely cumulative impeaching ragnar benson kassab ourts indulge presumptions favor validity verdict rowlik greenfield supp ed ew trials allowed simply verdict losing party come upon witness information theretofore unknown attorney see fendler goldsmith giving consideration effectiveness less severe sanctions impact preclusion evidence trial outcome case extent prosecutorial surprise prejudice whether violation willful may cases defendant legitimate objections disclosing identity potential witness see note preclusion sanction violation constitutional right present defense yale objections however raised advance trial response discovery request parties unable agree resolution presented federal rules criminal procedure rules adopted party may request protective order cause objecting discovery request see fed rule crim proc sup rule case issue concerning validity discovery requirement petitioner duty comply also indication petitioner ever objected prosecution discovery request case us rule way affected petitioner crucial decision call alibi witnesses added legitimate pressures leading course action rule compelled petitioner accelerate timing disclosure forcing divulge earlier date information petitioner beginning planned divulge trial nothing fifth amendment privilege entitles defendant matter constitutional right await end state case announcing nature defense entitles await jury verdict state deciding whether take stand williams florida trial judge also expressed concern discovery violations trials violations involved attorney otherwise contributed concern trustworthiness wormley testimony relevant unrelated discovery violations litigation however normally provide proper basis curtailing defendant constitutional right present complete defense noted illinois sanction preclusion reserved extreme cases people rayford illinois appellate explained exclusion evidence drastic measure rule civil cases limits application flagrant violations uncooperative party demonstrates deliberate contumacious unwarranted disregard authority schwartz moats app department transportation mainline center app reasons restricting use exclusion sanction extreme situations even compelling case criminal defendants due process requires defendant permitted offer testimony witnesses defense washington texas rights fundamental accused present witnesses defense chambers mississippi app see brookhart janis defendant constitutional right plead guilty trial confront adversary witness waived counsel without defendant consent doughty state ind record must show personal communication defendant chooses relinquish right jury trial cross app waiver right present trial justice brennan justice marshall justice blackmun join dissenting criminal discovery game integral quest truth fair adjudication guilt innocence violations discovery rules thus go uncorrected undeterred without undermining truthseeking process question case however whether discovery rules enforced whether need correct deter discovery violations requires sanction distorts truthseeking process excluding material evidence innocence criminal case conclude least criminal defendant personally responsible discovery violation alternative sanctions adequate correct deter discovery violations far superior arbitrary disproportionate penalty imposed preclusion sanction balancing test creates conflict interest every case involving discovery violation hold absent evidence defendant personal involvement discovery violation compulsory process clause per se bars discovery sanctions exclude criminal defense evidence addressing merits pause explicate take implicit conclusion defendant constitutional claims sufficiently well presented state courts support jurisdiction ante quite agree constitutional claims waived appellate illinois defendant appellate brief adequately presented sixth amendment claim see analysis case essentially due process clause see ante however explain conclusion constitutional claims waived trial conclude although matter illinois law defendant waived federal constitutional claims trial matter federal law waiver bar review legal challenge witness preclusion defendant raised trial one sentence motion new trial stating erred letting witness defendant testify jury record appellate illinois stated witness preclusion issue appeal whether trial abused discretion excluding testimony defense witness sanction violation discovery rules app appellate never addressed either compulsory process due process claims concerning witness preclusion even though briefs implicitly presented former claim expressly asserted latter alone may warrant assumption appellate implicitly held motion new trial stating erred preserved abuse discretion claim waived constitutional claims appellate illinois already reached holding identical case see people douthit app douthit stated despite appellate counsel excellent brief issue constitutionality applied criminal defendant portion rule rev stat ch par authorizing exclusion evidence failure comply discovery rule deem issue raised first time appeal waived nothing record indicate defense counsel ever raised constitutional objection extensive inchambers discussion summarized motion requests new trial solely ground erred ruling defendant call glen muench rocky reed testify defendant state intoxication time commission alleged burglary read motion raises question whether trial abused discretion exercising exclusion sanction failure raise issue including constitutional issue written motion new trial constitutes waiver issue urged ground reversal review citations footnotes omitted emphasis added conclusion appellate illinois deemed federal constitutional claims waived matter state law course mean waived matter federal law consistently held question defaults compliance state procedural rules preclude consideration federal question federal question henry mississippi specifically well established state possesses power disregard procedural default exceptional cases state failure exercise power particular case bar review williams georgia see also sullivan little hunting park henry supra illinois appellate courts possess power illinois rule provides plain errors defects affecting substantial rights may noticed appeal even though brought attention trial courts frequently rely provision address discretion issues waived trial see jenner tone martin historical practice notes following ann ch citing appellate cases decided examples cases invoking plain error alone see also people visnack app invoking substantial rights exception despite waiver apparently appellate declined exercise discretion deemed waiver binding since williams georgia decision bar review free address merits despite waiver ii merits start premise compulsory process clause sixth amendment embodies substantive right present criminal defense evidence jury see ante see also pennsylvania ritchie although thus join rejecting state argument clause embodies right subpoena witnesses agree assertion state argument supported plain language clause ante compulsory process clause provides criminal prosecutions accused shall enjoy right compulsory process obtaining witnesses favor plain language supports state argument one assumes natural reading constitutional language least meaningful right subpoena defense witnesses hollow protection indeed government simply refuse allow subpoenaed defense witnesses testify recognized last years right subpoena witnesses must mean right subpoena useful purpose thus necessarily implies substantive limitation government power prevent witnesses testifying right offer testimony witnesses compel attendance necessary plain terms right present defense right present defendant version facts well prosecution jury may decide truth lies washington texas emphasis added framers constitution intend commit futile act giving defendant right secure attendance witnesses whose testimony right use compulsory process due process clauses thus require courts conduct searching substantive inquiry whenever government seeks exclude criminal defense evidence ew rights fundamental accused present witnesses defense chambers supra exclusion criminal defense evidence undermines central truthseeking aim criminal justice system see nixon deliberately distorts record risk misleading jury convicting innocent person surely paramount value criminal justice system places acquitting innocent see winship demands close scrutiny law preventing jury hearing evidence favorable defendant hand compulsory process clause invalidate every restriction presentation evidence clause example require criminal courts admit evidence irrelevant crane supra testimony persons mentally infirm see washington texas supra evidence represents see nobles inquiry required compulsory process clause sometimes difficult course justify abandoning task altogether accordingly conducted searching substantive inquiries rationales underlying every challenged exclusion criminal defense evidence come date scrutiny led strike constitutionally unjustifiable rules prevent whole categories defense witnesses testifying basis priori categories presume unworthy belief rule introducing testimony alleged accomplice washington texas supra application hearsay rule statements originally made subsequently offered trial circumstances provided considerable assurance reliability chambers supra exclusion evidence bearing credibility voluntary confession crane supra per se rule excluding posthypnosis testimony rock supra based thorough review relevant case law defined standard governing constitutional inquiry last term rock arkansas concluding restrictions right present criminal defense evidence constitutional accommodate legitimate interests criminal trial process arbitrary disproportionate purposes designed serve rock arkansas supra quoting chambers supra question heart case whether precluding criminal defense witness testifying bears arbitrary disproportionate relation purposes discovery least absent evidence defendant personally responsible discovery violations question answered merely pointing discovery like compulsory process serves truthseeking interests compare ante last deny utility discovery truthseeking process see brennan criminal prosecution sporting event quest truth aiding effective trial preparation discovery helps develop full account relevant facts helps detect expose attempts falsify evidence prevents factors surprise influencing outcome expense merits case objectives accomplished compliance discovery rules exclusion material evidence discovery sanctions serve objectives discovery correcting adverse effects discovery violations deterring future discovery violations occurring sanctions excluding evidence sufficiently correct deter discovery violations reason resort sanction constitutes conscious mandatory distortion process whenever applied weinstein difficulties devising rules determining truth judicial trials colum rev use preclusion sanction corrective measure measure addressing adverse impact discovery violation might truthseeking case hand asserted two justifications bars defendant introducing testimony tested discovery see ante screens witnesses inherently suspect disclosed trial see ante first justification bearing case defendant insist right introduce witness testimony without giving prosecution opportunity discovery concedes trial within authority requiring witness testify first presence jury concedes trial granted prosecution continuance give sufficient time conduct discovery concerning witness proffered testimony see brief petitioner argues completely precluded introducing testimony nobles brown thus inapposite compare ante nobles defendant sought impeach credibility prosecution witnesses testimony defense investigator regarding statements witnesses made interviews investigator trial ruled investigator testify unless defense disclosed report investigator written summarizing interviews ibid properly rejected defendant claim right compulsory process violated district bar investigator testimony cf washington texas merely prevented respondent presenting jury partial view credibility issue adducing investigator testimony thereafter refusing disclose contemporaneous report might offer critical insights sixth amendment confer right present testimony free legitimate demands adversarial system one invoke sixth amendment justification presenting might emphasis added despite suggestions see ante preclusion issue justifiable theory trial exclude testimony presumes finds suspect first place trial purport rely presumption finding case rather ruling exclude testimony discovery violation judge stated whatever value jury trial great deal doubt mind veracity young man testified whether eyewitness scene sees guns wrapped know ray stops ray rate wormley going testify witness courtroom app emphasis added addition preventing jury hearing proffered testimony based presumptive apparent lack credibility antithetical principles laid washington texas reaffirmed rock arkansas criticized rules disqualified witnesses interest litigation effect suppressing truth washington texas supra noting isqualifications interest rested unstated premises right present witnesses subordinate interest preventing perjury erroneous decisions best avoided preventing jury hearing testimony might perjured even testimony available crucial issue conviction time truth likely arrived hearing testimony persons competent understanding may seem knowledge facts involved case leaving credit weight testimony determined jury believe latter reasoning required sixth amendment quoting rosen although persons identified defense witnesses trial may trustworthy categories persons surely presumption suspect jury prevented even listening testimony least arbitrary presumptions excluding accomplice testimony washington texas supra hearsay statements bearing indicia reliability chambers mississippi defendant posthypnosis testimony rock supra declared unconstitutional compare ante proper method illinois law washington texas supra addressing concern reliability prosecutor inform jury circumstances casting doubt testimony thus allowing jury determine credit weight wants attach testimony power take kind corrective measure undisputed defendant concedes allowed prosecutor comment defense failure disclose identity witness trial see brief petitioner leaving deterrence aside moment precluding witness testimony clearly arbitrary disproportionate purpose discovery intended serve advancing quest truth alternative sanctions namely granting prosecution continuance allowing prosecutor comment witness concealment correct adverse impact discovery violation truthseeking process moreover alternative sanctions unlike preclusion sanction distort truthseeking process excluding material evidence innocence course discovery sanctions must include corrective measures must also include punitive measures deter future discovery violations taking place otherwise parties little reason seek tactical advantages purposefully violating discovery rules orders violations caught corrected impose significant cost truthseeking process see supra ante long run conceivably outweigh burden truthseeking imposed preclusion sanction without means deterring discovery violations moreover criminal system continually interrupted distracted continuances corrective measures see ante light availability direct punitive measures however good reason least absent evidence defendant complicity countenance arbitrary disproportionate punishment imposed preclusion sanction central point keep mind witness preclusion operates effective deterrent extent possible effect outcome trial indeed employs part possibility distorted record cause jury convict defendant crime commit witness preclusion thus punishes discovery violations way disproportionate might result defendant charged capital offense convicted receiving death sentence received discovery violation arbitrary might another case involving identical discovery violation result defendant suffering change verdict charged lesser offense convicted receiving light suspended sentence contrast direct punitive measures contempt sanctions attorney responsible disciplinary proceedings gradate punishment correspond severity discovery violation arbitrary disproportionate nature preclusion sanction highlighted penalty falls defendant even though bore responsibility discovery violation case although ample evidence defense attorney willfully violated rule evidence defendant played role violation trial make effort determine whether defendant bore responsibility discovery violation indeed reading record leaves distinct impression main reason trial excluded wormley testimony belief defense counsel purposefully lied located wormley app worse yet trial made clear excluding wormley testimony response defense counsel actions case also response actions defense attorneys cases trial stated right going deny wormley opportunity testify going testify find blatent sic violation discovery rules willful violation rules also feel defense attorneys violating discovery courtroom last three four cases blatently sic going put stop one way absence evidence defendant played part attorney willful discovery violation directly sanctioning attorney fairer effective deterring violations excluding defense evidence compare ante threat disciplinary proceedings fines imprisonment likely influence attorney behavior far greater extent rather indirect penalty threatened evidentiary exclusion sanctions available rather punishing defendant rule trial sanctioned attorney rule ii provides wilful violation counsel applicable discovery rule may subject counsel appropriate sanctions see also app threatening disciplinary proceedings direct sanctions attorney particularly appropriate since discovery rule violated case places obligation comply discovery defendant directly attorney providing upon motion state defense counsel shall furnish state names last known addresses persons intends call witnesses sup rule emphasis added situation might different defendant willfully caused discovery violation points see ante defendants face prospect lengthy imprisonment arguably impossible deter direct punitive sanctions contempt explanation allowing defense witness preclusion evidence defendant bore responsibility discovery violation minimum obligated remand factfinding establish defendant responsibility deities may able visit sins father son agree courts permitted visit sins lawyer innocent client issue resolved analogizing tactical errors attorney might make failing put witnesses stand aided defense compare ante although sometimes held defendant bound tactical errors attorney makes fall short ineffective assistance counsel previously suggested client punished attorney misconduct fundamental differences attorney misconduct tactical errors tactical errors products legitimate choice among tactical options tactical decisions must made within adversary system system requires attorneys make operating presumption attorney choose course likely benefit defendant although decisions may later appear erroneous penalizing attorneys miscalculations generally exercise futility error usually visible hindsight time tactical decision made obvious incorrect choice prohibited one words adversary system often effectively deter attorney tactical errors want deter tactical decisions thus defense attorney makes routine tactical decision introduce evidence proper time defense seeks introduce evidence later deterrence measures may capable preventing untimely introduction evidence systemically disrupting trials jury deliberations final verdicts circumstances treating failure introduce evidence proper time procedural default binds defendant arguably means systemically preventing disruption binding defendant deters tactical errors better direct punitive sanctions binding defendant defense counsel procedural default definition eliminates disruption actual operation adversary system generally bears analysis outlined direct punitive sanctions available punish deter routine tactical errors however erroneous nature attorney decision sufficiently evident time system want deter attorney behavior directly sanctioning attorney malpractice bind defendant establishing malpractice also established ineffective assistance counsel rationales binding defendants attorneys routine tactical errors apply attorney misconduct attorney never faced legitimate choice includes misconduct option although may adversary process function effectively every tactical decision required client approval ante concern irrelevant client authority approve misconduct misconduct visible hindsight many tactical errors consequently misconduct amenable direct punitive sanctions attorneys deterrent prevent attorneys systemically engaging misconduct disrupt trial process need take steps inflict punishment defendant direct punitive sanctions also appropriate since determination misconduct occurred level penalty imposed primarily turns assessment attorney culpability rather procedural defaults assessment potential disrupting trial system case doubt willfully concealing identity witnesses one intends call trial attorney misconduct government seeks deter behavior instances attorney knows behavior misconduct legitimate tactical decision time occurs direct punitive sanctions attorney available see rule ii decision impose evidentiary exclusion penalty case clearly turned assessment attorney culpability see app people rayford app exclusion justifiable discovery violation deliberate one contends exclusion justified failure disclose wormley identity inadvertent short think scenario involve defendant willful violation discovery rule alternative sanctions fully vindicate purposes discovery without distorting truthseeking process excluding evidence innocence courts couple corrective measures subject testimony issue discovery adverse credibility inferences direct punitive measures proportional discovery violation directed actor responsible accordingly absent evidence defendant responsible discovery violation exclusion criminal defense evidence arbitrary disproportionate purposes discovery criminal justice per se unconstitutional thus agree balancing approach conclusion case exclusion constitutional balancing approach moreover unfortunate effect creating conflict interest every case involving willful discovery violation defense counsel placed position best argument make behalf client preclude defense witness punish personally case example defense attorney became noticeably timid judge threatened report actions disciplinary commission app argue sure bring disciplinary commission much appropriate sanction excluding witness might get client acquitted see expect defense counsel case act vigorous advocates interests clients interests adverse seems particularly ironic approve exclusion evidence case time several members expressed serious misgivings evidentiary costs exclusionary rules contexts surely deterrence constitutional violations less important deterrence discovery violations said evidentiary costs significant imposed prosecution turn head justice harlan termed fundamental value determination society far worse convict innocent man let guilty man go free winship concurring opinion discovery rules important means helping criminal system convict guilty acquit innocent precluding defense witness testimony sanction defense counsel willful discovery violation directly subverts criminal justice basing convictions partial presentation facts nixon also arbitrary disproportionate purposes served discovery rules discovery sanctions today thus sacrifices paramount values criminal system misguided unnecessary effort preserve sanctity discovery may never know certain whether defendant bridges brother fired shot defendant convicted know however jury convicted defendant permitted hear evidence placed gun bridges brother hands contradicted testimony bridges brother possessed weapons evening defense counsel delay identifying witness innocent man may serving years prison dissent although rock addressing specific issue defendant right offer testimony derived standard articulated general compulsory process case law theory right present one testimony extended least far right present testimony others illinois rule alone supplies broad array available discovery sanctions party failed comply applicable discovery rule may order party permit discovery material information previously disclosed grant continuance exclude evidence enter order deems circumstances ii wilful violation counsel applicable discovery rule may subject counsel appropriate sanctions see people santucci ultimate decisions fact must fairly left jury must determination credibility witnesses weight afforded testimony end province judge criminal case convey opinions matters jurors word deed people heidorn app trial judge wide discretion conduct trial must make comments insinuations word conduct indicative opinion credibility witness cf people rayford app reasons cited illinois courts forbidding judicial comment apply force prosecutorial comment see santucci supra heidorn supra precluding witness based solely judge belief witness lacks credibility might also implicate constitutional right jury trial usurps jury central function assessing credibility witnesses constitutional right jury trial mean little judge exclude defense witness whose testimony credit second day trial tuesday march defense counsel moved amend answer discovery include alfred wormley defense witness stating defendant told wormley earlier able locate wormley previously app next day wormley testified defense counsel visited home served subpoena wednesday march five days trial began witness preclusion sanction thus justified theory defendant waived right introduce wormley failing name prior trial indeed far procedural default exclusion evidence unusual sanction applied drastic cases people rayford app decision whether apply lies discretion trial app case also note balancing approach create uncertainty spawn unnecessary litigation make difficult supervise lower courts moreover exclusion criminal defense evidence also important disadvantage inviting claim every case applied direct sanctions attorney yield opportunity disrupt final verdicts justice blackmun dissenting join justice brennan dissenting opinion understanding least part confined reach general rules wish opinion express position permissible sanctions noncompliance rules designed specific kinds evidence example rule case state legitimate interests might well occasion result different obtain factual context present case