‘Double Blind’ Lineups Guard Against Mistaken Identity

By Det. Ivan Kaminsky, Adjunct Faculty – Criminal Justice

CTU Criminal Justice Double Blind LineupTruth is the goal in every criminal investigation. In order to prove it, many types of evidence are used, including eyewitnesses.  But, as Police Chief Magazine noted in 2009  “Unfortunately, mistaken eyewitness identification is the single greatest cause of wrongful convictions nationwide. Mistaken eyewitness identification has been reported to play a role in more than 75% of the convictions that have been overturned by DNA testing.”  It is critical for a professional investigator to do everything within their power to ensure proper identification.

The investigator must also be poised to counteract moves by defense attorneys that might cloud the truth.  A defense attorney’s job is not to prove the facts, but rather to advocate for their client and create a “reasonable doubt” in the mind of the jury.  

In order to keep the focus on truth, investigators are not only turning to sequential photo lineups but they are presenting them with a “double blind” methodology to ensure accuracy. The witness seeing the lineup is not privy to the order or location of the suspect’s photo. When the administrator of the lineup is not aware of the location either, essentially both are blind, making the process “double blind.” 

We have all experienced a time in our life when a person knows something we do not, and as hard as they might try to remain neutral, their face often hints at the answer.  During criminal investigations we must guard against this tell.  Through the use of a double blind lineup, we are one step closer to uncovering the truth.

Some still believe that we shouldn’t let defense attorneys or claims about unintentional hinting influence us.   I don’t believe it is an intentional choice we get to make.   The benefit of the double blind lineup is that it not only keeps investigators from inadvertently influencing the witness, but it makes it impossible for them to do so, and thus, keeps the process fair.

Ivan Kaminsky is an adjunct instructor in the Criminal Justice program at Colorado Technical University. A detective with the Chandler, AZ police department, he holds a variety of professional memberships and certifications in investigative techniques and tactics. He holds his undergraduate degree from Arizona State University and his M.S. degree in educational leadership from Northern Arizona University.

Image credit: The Blaze