Journal of Emerging Scholarship

This literature review examines the scientific foundations, investigative value, and ethical and legal risks of using “trashed” or abandoned DNA, biological material left on discarded items such as tissues, cigarette butts, and food waste in criminal investigations. Drawing on forensic science research, case examples, and legal scholarship, the review explains how discarded DNA can be collected, processed, and compared through methods such as STR profiling, CODIS searches, and, increasingly, genetic genealogy techniques. Trashed DNA has helped solve cold cases, identify perpetrators, and support post-conviction exonerations, demonstrating its potential to advance public safety and justice outcomes. However, the expanded use of discarded DNA also raises significant concerns about privacy, informed consent, and constitutional protections. Because abandoned property typically carries diminished expectations of privacy, law enforcement may obtain DNA from trash without a warrant, creating opportunities for misuse and mission creep beyond serious violent crime. Additional risks include the exposure of sensitive medical or familial information, increased surveillance of communities, and the implication of relatives through genealogical searching. The literature review argues that, while trashed DNA can be a powerful investigative tool, its continued growth without clear safeguards threatens civil liberties and public trust. It recommends establishing statutory standards for collection and use, limiting applications to serious offenses, strengthening oversight and transparency, and expanding research on accuracy, bias, and Fourth Amendment implications to better balance investigative benefits with ethical boundaries.