INTRODUCTION

Eyewitness identification testimony is some of the most compelling evidence a jury can hear, but it can also be some of the most unreliable. A review of DNA exoneration cases demonstrates that mistaken identifications are a leading cause of wrongful convictions. The scientific study of eyewitness identification and memory helps to explain why. Researchers have unearthed a set of risk factors that make witnesses more likely to be mistaken—known as “estimator” and “system” variables.

Yet despite the frailties of eyewitness identification testimony, recognized by this Court and courts across the country, it remains powerfully persuasive to jurors. Juries have even convicted innocent individuals based on mistaken identifications in the face of exculpatory DNA evidence. Moreover, although the scientific community has come to a consensus about certain variables that make eyewitness identifications less likely to be accurate, many of their findings continue to prove counterintuitive to laypeople. Expert testimony is needed to educate jurors about these risk factors.

This Court has recognized the role that misidentifications play in wrongful convictions and “encouraged” the admission of eyewitness expert testimony. People v. Santiago, 17 N.Y.3d 661, 669 (2011). Nonetheless, lower courts (like the courts here) have taken this Court’s decision in People v. LeGrand, 8 N.Y.3d 449 (2007), as license to exclude eyewitness experts whenever the trial court thinks there is “sufficient corroborating evidence” supporting the identification—even when expert testimony would in fact aid the jury. This corroboration rule treats eyewitness expert testimony unlike any other type of evidence and is fundamentally flawed.

Precluding or limiting eyewitness expert testimony based on the supposed strength of the other evidence—evidence that has not yet been tested at trial — deprives jurors of the opportunity to make fully informed judgments about the evidence and, accordingly, increases the probability of wrongful convictions. In cases where identification is at issue and estimator or system variables are implicated, experts can offer crucial evidence, explaining the frequent flaws of eyewitness identifications and illuminating the often-counterintuitive factors that undermine their reliability. The admissibility of such probative evidence should not depend on how a court views the strength of the prosecution’s case, but instead on whether it would aid the jury in making a reliable determination.

Introduction

Eyewitness accounts can be very convincing in court, but they are not always accurate. Studies of cases where DNA evidence cleared wrongly convicted people show that mistaken identifications are a main reason for these errors. Scientific research into how eyewitnesses identify people and how memory works helps explain why this happens. Scientists have found factors that increase the chance of a witness making a mistake. These are called "estimator" variables and "system" variables.

Even though courts across the country know that eyewitness testimony can be flawed, juries still find it very persuasive. Juries have even convicted innocent people based on mistaken identifications, even when DNA evidence showed they were not guilty. Also, while scientists agree on factors that make eyewitness identifications less accurate, many of these findings are surprising to people who are not experts. Expert testimony is therefore needed to teach jurors about these risk factors.

The court has acknowledged that incorrect identifications lead to wrongful convictions and has supported the use of eyewitness expert testimony. However, some lower courts have used a previous court decision as a reason to block eyewitness experts if the court believes there is enough other evidence to support an identification. This happens even when an expert's testimony would actually help the jury. This rule about "corroboration" treats eyewitness expert testimony differently from other types of evidence and has serious problems.

Preventing or limiting expert testimony on eyewitness identification because of other evidence, especially evidence not yet examined in a trial, stops jurors from making fully informed decisions. This then increases the chance of wrongful convictions. When identification is a key issue and risk factors are present, experts can provide important information. They can explain common problems with eyewitness identifications and clarify factors that often surprisingly make them less trustworthy. Whether such important evidence should be allowed should not depend on how a court sees the strength of the prosecution's argument. Instead, it should depend on whether the evidence would help the jury make a reliable decision.

Introduction

Eyewitness accounts can be very convincing in court, yet they are often inaccurate. Studies of cases where DNA evidence cleared wrongly convicted individuals show that mistaken eyewitness identifications are a primary reason for these errors. Scientific research into how people identify others and how memory works helps explain why this happens. Researchers have found several factors that increase the chance of a witness making a mistake. These factors are called "estimator" and "system" variables.

Even though courts across the country acknowledge the weaknesses of eyewitness testimony, juries still find it very persuasive. There have been instances where juries convicted innocent people based on incorrect identifications, even when DNA evidence proved otherwise. Furthermore, while scientists agree on certain factors that reduce the accuracy of eyewitness identifications, many of these findings are not obvious to most people. Therefore, expert testimony is necessary to inform jurors about these risk factors.

The court has previously noted the role of misidentifications in wrongful convictions and has supported allowing expert testimony on eyewitness identification. However, lower courts have sometimes used a previous ruling to exclude eyewitness experts if they believe there is enough other evidence to support the identification. This practice occurs even when expert testimony could clearly help the jury. This rule for corroboration treats eyewitness expert testimony differently from other types of evidence and has significant problems.

Preventing or limiting expert testimony on eyewitness identification based on the perceived strength of other evidence, which has not yet been examined in court, stops jurors from making fully informed decisions about the evidence. This increases the chance of wrongful convictions. In cases where identification is a key issue and estimator or system variables are involved, experts can provide vital information. They can explain common flaws in eyewitness identifications and highlight factors that often subtly undermine their reliability. The decision to allow such important evidence should not depend on how a court views the prosecution's case, but rather on whether it would help the jury make a reliable judgment.

Introduction

Evidence from eyewitness identification is often very convincing to a jury, but it can also be very unreliable. Studies of cases where DNA evidence cleared individuals show that mistaken identifications are a main reason for wrongful convictions. The scientific study of eyewitness identification and memory helps explain why this happens. Researchers have found several factors, called "estimator" and "system" variables, that increase the chance of a witness making a mistake.

Despite the known weaknesses of eyewitness identification, it remains very powerful for jurors. Juries have even convicted innocent people based on mistaken identifications, even when DNA evidence showed they were not guilty. Scientists generally agree on certain factors that make eyewitness identifications less accurate, but many of these findings are not obvious to most people. Expert testimony is needed to teach jurors about these risk factors.

The courts have acknowledged that misidentifications cause wrongful convictions and have supported the use of expert testimony about eyewitness identification. However, lower courts have often used a past decision to exclude eyewitness experts when they believe there is enough other evidence supporting the identification. This practice prevents expert testimony from helping the jury and is a flawed way to handle such evidence.

Blocking or limiting expert testimony based on the supposed strength of other evidence—which has not yet been fully examined in court—prevents jurors from making fully informed decisions. This increases the chance of wrongful convictions. In cases where identification is important and certain risk factors are present, experts can provide key information. They can explain common problems with eyewitness identifications and clarify factors that often secretly affect their reliability. Whether such important evidence should be allowed should depend on if it helps the jury make a reliable decision, not on how a court views the strength of the prosecution's case.

Summary

Eyewitnesses can help solve crimes, but sometimes they make mistakes. When people are wrongly put in jail, it is often because an eyewitness made a mistake. Scientists study how people remember things to understand why these mistakes happen. They found things that make it more likely for an eyewitness to be wrong.

Even when eyewitnesses make mistakes, juries often believe them. Juries have sometimes found innocent people guilty, even when DNA showed they were innocent. Experts can help explain to juries why eyewitnesses can be wrong.

Courts have said that experts can talk about eyewitness mistakes. But some courts still do not let experts speak if they think other proof is strong enough. This way of doing things is not fair and can lead to innocent people going to jail.

When there are questions about an eyewitness's memory, experts can help. They can explain to juries how mistakes happen and why some things make eyewitness memories less reliable. This important information should always be shared with the jury, no matter how strong the other proof seems.