University of Chicago Law School
Law enforcement officers will often obtain shed or abandoned DNA samples from persons who they suspect have committed crimes, but lack sufficient evidence to arrest or detain such persons. When utilizing abandoned or shed DNA for criminal investigative purposes, there are two state actions which arguably trigger Fourth Amendment protection. First, the collection of the biological material which contains a person’s DNA might be considered a search under the amendment. Courts, however, have uniformly rejected this argument. For example, when police are interested in determining whether a suspect may be connected with an unsolved crime for which they collected a DNA sample from the crime scene, they will covertly obtain the suspect’s DNA from a fast-food wrapper or hair sample taken from a barber-shop floor. To date, judges have concluded that persons have discarded the DNA-laden cells obtained by police in these circumstances, and thus under Fourth Amendment law, retained no privacy interest in the item seized by police.
Maryland v. King: Terry v. Ohio Redux,
Supreme Court Review
Available at: https://scholarship.law.bu.edu/faculty_scholarship/222