The Supreme Court announced Friday that it will decide whether it's legal for police to collect DNA samples from people under arrest, a case that could have nationwide implications on the question of privacy versus public safety.

The justices announced that they will review a Maryland court decision that effectively barred the warrantless collection of genetic material from suspects who have not yet been convicted of a crime, a procedure used around the country in hopes of cracking old cases.

Courts have consistently upheld DNA collection from those convicted of a crime. But the federal government and 27 states also have laws that allow the collection of DNA from people arrested but not yet convicted.

Maryland began collecting samples from people arrested for violent crimes in 2009 and authorities took a cheek swab from Alonzo King Jr., who was arrested on assault charges. Police found out the sample matched the DNA of a rapist from a 2003 rape in Salisbury, Md. King was later found guilty in the 2003 attack and sentenced to life in prison.