Blind studies and procedures are the gold standard of evaluating the quality and reliability of scientific results. Unfortunately, this has long been lacking in forensic science. Fortunately, strides are being made to introduce blind testing to forensics, most notably in the Houston Forensic Science Center (HFSC).
Currently, forensic scientists are tested periodically on their knowledge and ability through proficiency tests. However, scientists typically are aware they are completing a proficiency test and not case work. This allows for the Hawthorne effect to play a role in the testing, or the phenomena of a person behaving differently when they know they are being observed. Blind testing in forensic science will allow for blind samples to be included with case work in a manner that scientists cannot distinguish between a blind and a real case. This will help distinguish whether or not a laboratory adheres to guidelines and whether best practices are used in a day-to-day setting, as opposed to simply during an anticipated exam.
This article describes the efforts of Dr. Peter Stout, the HFSC’s chief executive officer (and former member of the NC Forensic Science Advisory Board), to implement a “blinds program.” So far, 329 blind samples have been integrated into normal casework in the firearms, toxicology, DNA, fingerprint, and digital forensic sections of the lab. In 2018, the lab plans to grow the program to 800 blind tests per year, or 5 percent of the lab’s workload.
Disguising a blind as a case sample is not a simple task, as the Forensic Magazine article describes. In addition to the challenge of creating a case submission that appears authentic, another particularly challenging aspect has been determining whether the blind samples could be searched in databases like AFIS, NIBIN, and CODIS.
At the HFSC, no errors have yet been reported in the testing of a blind. Use of blind tests will allow the lab to begin reporting error rates and confidence intervals, which will strengthen the testimony of analysts and allow them to answer questions about reliability of their work.
If you’ve made it this far in the post and are still wondering about the title, “Houston, in the blind” refers to a phrase used by astronauts when they aren’t receiving any response from ground control. The phrase indicates that they will continue to communicate, not knowing if ground control is receiving their message. My hope for forensic science is that communications about blind testing will not be “in the blind.”