When you interview as many people as I have you often get asked: were they (the eyewitness) telling the truth? For the first few years I relied on my gut feeling to answer that question; eventually I decided to take a more scientific approach to see if I could remove my visceral opinion. I’ve been an armchair psychologist since completing my BA in Behavioral Sciences and Criminology in 2001, so I approached this issue as a study project. I analyzed my sketch interview technique and focused on the areas of the interview that would give me an idea of whether the sketch would be reliable in an investigation. I called this study my Composite Sketch Interview Analysis (or CSA). My hypothesis: Complete an analysis of my sketch interview with the eyewitness and I can learn whether my sketch is reliable.
I conducted my research from 2004 thru 2011 and shared my results of over 1,000 sketch interviews with more than 300 investigators and a few deputy district attorneys. Many of them were intrigued with my findings and were eager to learn about the reliability of their eyewitness. I had established a protocol with the investigators I worked with to help them gain confidence in utilizing a cognitive sketch for their investigations: I made it simple: 1. Ask the eyewitness, if you saw him (the suspect) again would you recognize him? If they said yes, the eyewitness was a good candidate for a sketch interview. If they said no—they were not. Anything in between would require more investigation. 2. Tell me about the crime type, date and time of the event and name of the eyewitness. I did not want to hear about their opinions on the investigation nor about their take on the statements of the eyewitness. I communicated through email for most cases and eventually I created an online form so that I would receive only the pertinent information. I wanted to treat each sketch interview request as a unique and objective task.
For the first year of my research I said nothing to the detectives to ensure the objectivity of my process. I met with my eyewitnesses for their sketch interviews and after each session I would take a few minutes and complete my CSA form (on FileMaker Pro). After more than 75 entries I got a call from a detective telling me that his victim on a previous case had lied. I get calls like this as a courtesy from detectives to keep me in the loop about how the investigation is going. I pulled out my black binder filled with the completed CSA forms and I looked for the corresponding case number. I found the CSA form and noted the score and made a note in red: “victim lied.” I received calls about identifications and lying witnesses over the next seven years and jotted down the notes on the CSA forms. My findings had been validated and it gave me confidence to reveal my study to the investigators and DDA’s alike. Many of the detectives were keen on using my ‘reliability’ tool. Detectives have a tough job with deciding whether to confront an eyewitness about the validity of their statements and many rely on their experience and instinct to take the plunge and call someone a “liar.” The consequences can be devastating to an investigation. From now on detectives can request a sketch from me and inquire about the reliability of the sketch. If the sketch is deemed unreliable they can feel pretty confident in confronting the eyewitness about the inconsistencies in their statements. Instead of asking me if I think the person was lying, they can ask me about the reliability of my sketch and make their own decision moving forward. Having a highly qualified independent source to measure the reliability of the statement of the eyewitness is a powerful tool.