Police departments across the United States are changing the format of suspect lineups, although new research from Illinois says this procedure may be ineffective.
The study, conducted by the Illinois State Police, examined a new eyewitness identification procedure called a double-blind, sequential lineup. When police put together a lineup, they mix “fillers,” or people who aren’t necessarily suspects, in with the actual suspect to see if the witness can make a selection.
In the sequential method, the witness views suspects individually rather than as a group, and neither the witness nor the administrator know the suspect’s identity. The witness tries to identify a suspect by looking at photos or people in person. The study found that witnesses were more likely to identify the suspect in a group lineup format.
Sixty percent of witnesses who viewed a traditional group lineup were able to identify the suspect, while 45 percent of witnesses were able to identify the suspect in the sequential lineup. Forty-seven percent of witnesses who viewed the sequential lineup didn’t identity anyone as a suspect.
The study was conducted for a one-year period at police departments in Evanston, Chicago and Joliet. Professor Roy S. Malpass of the University of Texas at El Paso has studied eyewitness identification for the past 20 years and designed the Illinois study. Malpass said police departments must be careful when adjusting lineup procedures.
“If you’re going to decrease false identifications, then you’re going to decrease correct identifications,” he said.
Previous research has found sequential lineups to be superior to the simultaneous method. But these classroom studies were done under controlled settings, Malpass said.
“In the lab we know the identity of the guilty party,” he said.
Pressure to develop more successful lineups has led some cities to adopt the sequential procedure. Police in Boston no longer use the simultaneous method, and police in Washington D.C., may make the sequential method mandatory.
In 2002, police in Santa Clara, Calif., switched from simultaneous lineup to the sequential method at the county district attorney’s recommendation. Captain Tom Clark said the switch was a “fairly benign” process.
“For what you’re getting out of it, the switch is not that big of a deal,” he said. “It’s just a matter of changing the way we conduct our police lineups.”
Evanston police did not completely change their lineup format for the study. Odd-numbered cases were selected for the sequential method, and police continued to use the group procedure for even-numbered cases.
Deputy Chief of Evanston Police Department Joseph Bellino said one pitfall of the sequential method is that it requires a “blind administrator.” This means the lineup must be administered by someone from the police department who doesn’t know the suspect’s identity. This eliminates the possibility that the officer will influence the witness.
But some small- or medium-sized departments may not have enough employees to serve as blind administrators, Bellino said.
“When you’re striving to keep police officers on the streets and you have to pull additional resources to meet the needs for sequential lineups, it defeats the purpose,” Bellino said.
But Clark said his department, with 150 officers on staff, meets the demands of sequential lineups. In addition to personnel problem, Bellino also said more research must be done.
“We’ve just started to scratch the surface regarding eyewitness identifications,” he said.
Reach Vincent Bradshaw at [email protected].
