Document Type



Criminal Law | Evidence


Hair has long been collected from crime scenes as part of trace evidence. Originally, hair was used for some exclusionary purposes—only general qualities about an unknown source could be determined. Eventually, DNA was used to help identify the source but only if the root was still attached. Within the last two years, however, two major studies have used proteomics—the study of human protein sequences—to extract and identify protein sequences in an unknown source in order to match it to a known source. These two studies support the same hypothesis: proteomics is currently a viable method for narrowing down the source of the hair and will soon be able to identify an individual source. While the science is about a decade away from being comparable to nuclear DNA, the potential of proteomics is undeniable. This paper explores the current status, methods, and future of the science as well as the impact it may have on forensic investigation and criminal prosecution. This paper also explores the potential admissibility of expert testimony on proteomics for identification.