In thousands of criminal cases each year, the prosecution’s main evidence consists of eyewitness identification. And in over half the cases in which courts free innocent people from prison, mistaken eyewitness identification was the cause of conviction. For better or worse, eyewitness identification often determines the outcome of criminal cases.
Because of the importance of eyewitness identification, evidence rules allow eyewitnesses not only to identify suspects at trial, but also to testify about pretrial identifications. Evidence of multiple, consistent identifications tends to strengthen a prosecutor’s case. On the other hand, because of the rampant problem of mistaken identifications, defendants are allowed to educate jurors about factors tending to undercut the accuracy of eyewitness identifications. (For information on the process of indentification in criminal cases, including ways defendants can handle identification requests and challenge IDs, see Nolo's page for Eyewitness Identification issues.)
The three most common pretrial eyewitness identification procedures are:
Lineups. A lineup typically consists of five to six people. Usually one is the suspect, while the others may be police officers or other “decoys” who bear a resemblance to the suspect or fit the description that eyewitnesses gave the police.
Photo identifications. This procedure calls for eyewitnesses to view photographs, typically mugshots, in a police department’s files. The police may resort to photo identifications after bringing the suspect into custody or when they don’t yet have enough information to make an arrest.
Showups. A showup is a one-on-one identification procedure. The eyewitness views a single suspect, perhaps at a police station or even at the crime scene. This procedure is the most vulnerable to attack because of its obvious suggestiveness.
Typically, eyewitnesses testify about their ability to view the suspect during or soon after the crime, then pick out the defendant in the courtroom as the perpetrator. (Of course, they rarely fail the in-court “test” since the defendant is sitting at counsel table!)
Evidence rules allow prosecutors to bolster eyewitnesses’ in-court identifications by presenting evidence of consistent pretrial identifications. For example, an eyewitness may testify as follows:
Question: And what happened when you came to the police station the day after the robbery?
Answer: Officer Smith sat me at a computer and asked me to look through photos and tell him if I recognized anyone.
Question: And did you recognize anyone?
Answer: Yes, as soon as I saw the photo of the defendant. I must have looked at 50 or 60 photos by that time, but when I came to the defendant’s photo, I stopped looking and immediately told the officer that this was the robber.
Of course, the defense can ask questions about an eyewitness’s failure to make a positive identification. For example, a portion of a defense attorney’s cross-examination of an eyewitness may go as follows:
Question: You’ve testified today that the defendant is the person who robbed the bank, right?
Question: But you attended a lineup less than two weeks after the robbery, right?
Answer: That’s true.
Question: And the defendant was in that lineup, wasn’t he?
Answer: He was.
Question: Yet at that time you told the police that you didn’t recognize anyone in the lineup as the robber, didn’t you?
Answer: That’s correct, but--
Question: Thank you. You’ve answered my question.
If a judge concludes that a pretrial identification procedure was unfair, an eyewitness cannot testify at trial to having identified the defendant before trial. In an extreme case, a judge may decide that a pretrial identification was botched so badly that an eyewitness won’t even be allowed to make an identification at trial.
Example: Shortly after receiving a report of a convenience store robbery, the police arrest Stan Desside, who generally matches the clerk’s description. Bringing Desside to the store, the police tell the clerk, “This guy matches the description you gave. He’s got a record a mile long, and his alibi doesn’t hold water. Just tell us we’ve got the right guy, and we’ll haul him off to jail so you won’t have problems from him again.” The clerk then says, “Okay—then that’s the one who robbed me.” A judge would presumably rule that the clerk can’t testify to the out-of-court identification. Moreover, the risk is so great that the unfair procedure tainted the clerk’s memory that the clerk shouldn’t even be allowed to identify Desside at trial.