In recent years, DNA exonerations have brought to light what are perceived as flaws in police photo lineup procedures. In some cases where DNA evidence has later cleared an incarcerated suspect, one of the factors in the original conviction may have been the false identification of the suspect in a photo lineup by an eyewitness.
Advocacy groups have seized upon these errors, and certain social research studies, to attempt to initiate changes in how law enforcement conducts its photo identifications.
A current concern about eyewitness identifications pits the accuracy of traditional-type photo lineups against the newer sequential, double-blind presentations of photographs in photo lineups.
Although across the country there have been studies commissioned, policies examined, and new laws enacted, controversy persists that there has been a rush to change eyewitness identification procedures in the absence of real world data.
In a traditional photo lineup, the officer or detective who shows the photo array knows which is the suspect’s photograph. Also in the traditional method, a simultaneous photo lineup shows an eyewitness the photograph of the suspected person together with five to seven other persons’ photographs.
The other persons, called fillers, should reasonably resemble the suspect. All the photos are presented together, usually on the same page. The suspect’s position on the page is randomly selected.
Conversely, a double-blind photo line up means that the officer showing the photographs does not know the identity of the suspect. In a sequential photo lineup, the photographs of the suspect and fillers are each presented separately and in a random order.
The comprehensive 1999 U. S. Department of Justice’s National Institute of Justice study Eyewitness Evidence: A Guide for Law Enforcement articulates either method of photo lineup presentation as valid.
Advocates of change believe, mostly through “common sense” logic and anecdotal academic studies, that sequential, double-blind photo lineups will be more accurate and will lead to fewer (or no) false identifications by witnesses.
Unfortunately, a 2006 Illinois State Police study of actual police lineups conducted by trained officers gave different results. Illinois enacted legislation to conduct a study of traditional verses sequential, double-blind lineups. The study collected data for a year, starting in late 2004.
Surprisingly, false identification of filler (innocent) subjects rose to 9.2% in sequential lineups from only 2.8% in traditional lineups. At the same time, positive identification of known suspects dropped to 45% in sequential lineups from 59.9% in traditional lineups.
Since the Illinois research, similar results were found in other real world studies in Brooklyn and Queens, New York and Hennepin County, Minnesota in actual live and photo criminal lineups.
Some interesting information came from these studies. In the Illinois study, 75% of the officers did not prefer one method of presentation over the other. They felt that if an eyewitness could identify the suspect, either type of lineup would suffice.
The Brooklyn, Queens, and Hennepin County studies found no evidence officers were either deliberately or incidentally influencing eyewitnesses during actual lineups.
One focus of advocacy groups has been that false identifications happen because the police may be either intentionally or unintentionally influencing witnesses during lineups. If it is intentional, it is police misconduct. If unintentional, it is flawed police procedure.
This line of thinking blames law enforcement and ignores the possibility that sometimes eyewitnesses are just plain mistaken.
Previous academic research studies were done by showing college students and volunteers simulated crime videos and conducting photo lineups afterward. These research studies based their findings on imaginary scenarios, not real criminal events and their emotional component.
Unfortunately, these academic research studies are the data upon which advocates have based their efforts to force legal mandates on law enforcement to make substantive changes to eyewitness identification procedures.
A positive result of the controversy is that law enforcement is taking a hard look at how photo lineups are conducted. To improve the effectiveness of lineups, some jurisdictions are adopting standard language for photo pack instructions.
These instructions are given to eyewitnesses before they view the photographs and include statements that:
- The witness will be asked to look at a set of photographs.
- The person who committed the crime may not be shown.
- It is just as important to clear innocent persons as identify guilty parties.
- Persons may not appear as they did at the time of the incident, as hair or clothing may have changed.
- Regardless of whether the witness chooses a subject, the investigation will continue.
Law enforcement agencies are also concentrating on more specific training for officers in the construction and presentation of police photo lineups.
The real world studies concluded that the accuracy differences between traditional lineups and sequential, double-blind photo lineups need further study. The DOJ NIJ is conducting additional research into the topic.
In the absence of clear empirical data, advocacy-driven changes to photo lineup protocols are unwarranted until the controversy is resolved.
Randall is a twenty-three year sworn police officer in a mid-sized Florida police department. His experience includes six and a half years as a Detective investigating Property Crimes and Crimes Against Persons.