“challenges this presumption of innocence”
The Supreme Court disagrees. In 2013, the Court ruled in Maryland v. King that taking DNA upon arrest does not violate the Fourth Amendment’s protection against unreasonable searches and seizures. Since then, warrantless DNA collection and comparison has been widely practiced, much to the chagrin of civil liberties groups such as the American Civil Liberties Union.
According to data from the National Conference of State Legislatures, 20 states do not collect DNA upon any arrest. Of the remaining 30 states that do, most limit this collection to felony arrests, while eight also include specific misdemeanors. Even among felony arrests, the relevance of collecting DNA can vary widely: using DNA from a marijuana trafficking arrest to compare against samples from the crime scene of a serial murder is unjustifiable.
