Police May Not Need a Warrant to Rummage Through Your Trash, But Warrantless Collection of DNA Is Unconstitutional

This week, we filed an amicus brief in a South Dakota case arguing that the Fourth Amendment prohibits the police from surreptitiously collecting our DNA without a warrant. This case is one of the first to challenge the collection of DNA from a free person after results of a genetic genealogy database search linked her to a crime.

In the case, prosecutors have charged Teresa Bentaas, a lifelong Sioux Falls resident, with first degree murder for abandoning a newborn 39 years ago. To link Ms. Bentaas to the baby, police secretly collected her DNA from items they found in her trash, extracted and sequenced it, and then compared it to the baby’s. Ms. Bentaas was not under arrest or in police custody at the time they collected and searched her DNA, so, unlike an arrestee, there can be no argument her Fourth Amendment rights were in any way “diminished.” 

Ms. Bentaas’s attorneys have filed a motion to suppress the DNA evidence and all evidence collected by the police after that, arguing this secret and warrantless rummaging and data...