For purposes of due process, a pretrial identification isn’t suppressible unless the product of improper law enforcement activity.
We have not extended pretrial screening for reliability to cases in which the suggestive circumstances were not arranged by law enforcement officers. Petitioner requests that we do so because of the grave risk that mistaken identification will yield a miscarriage of justice.1 Our decisions, however, turn on the presence of state action and aim to deter police from rigging identification procedures, for example, at a lineup, showup, or photograph array. When no improper law enforcement activity is involved, we hold, it suffices to test reliability through the rights and opportunities generally designed for that purpose, notably, the presence of counsel at postindictment lineups, vigorous cross-examination, protective rules of evidence, and jury instructions on both the fallibility of eyewitness identification and the requirement that guilt be proved beyond a reasonable doubt.
Perry was identified by what the Court describes as “mere happenstance” – Perry was standing next to a police officer investigating a reported break-in of a car in a parking lot, when a witness viewed them from inside her apartment and identified Perry as the perpetrator, without police involvement. (“As the trial court found, the witness pointed out the defendant from her apartment window without any inducement from the police, Summary Order, p. 1.) The long and short of it: due process requires suppression of an identification only where the identification is treaceable to police misconduct. Perry was identified at was what, in effect a single-person “showup,” a procedure that, if arranged by the police, will be considered “suggestive” by definition, the inquiry becoming whether it was “necessary.” State v. Dubose, 2005 WI 126,, 285 Wis. 2d 143, 699 NW 2d 582, ¶2 (“We hold that evidence obtained from such a showup will not be admissible unless, based on the totality of the circumstances, the showup was necessary. A showup will not be necessary, however, unless the police lacked probable cause to make an arrest or, as a result of other exigent circumstances, could not have conducted a lineup or photo array.”). But Perry’s “showup” wasn’t arranged by the police, so it isn’t suppressible as a matter of due process.
We have concluded in other contexts, however, that the potential unreliability of a type of evidence does not alone render its introduction at the defendant’s trial fundamentally unfair….
Our unwillingness to enlarge the domain of due process as Perry and the dissent urge rests, in large part, on our recognition that the jury, not the judge, traditionally determines the reliability of evidence. See supra, at 7. We also take account of other safeguards built into our adversary system that caution juries against placing undue weight on eyewitness testimony of questionable reliability. These protections include the defendant’s Sixth Amendment right to confront the eyewitness. See Maryland v. Craig, 497 U. S. 836, 845 (1990) (“The central concern of the Confrontation Clause is to ensure the reliability of the evidence against a criminal defendant.”). Another is the defendant’s right to the effective assistance of an attorney, who can expose the flaws in the eyewitness’ testimony during cross-examination and focus the jury’s attention on the fallibility of such testimony during opening and closing arguments. Eyewitness-specific jury instructions, which many federal and state courts have adopted,7 likewise warn the jury to take care in appraising identification evidence. …
State and federal rules of evidence, moreover, permit trial judges to exclude relevant evidence if its probative value is substantially outweighed by its prejudicial impact or potential for misleading the jury….