Golden State Killer apprehended after 40 year probe; DNA taken from trash can led to arrest of former police officer

California: DNA from a tissue left in a trash can led authorities in April to arrest a former police officer suspected of being California's notorious Golden State Killer, according to warrants released on Friday.Documents released by a judge at the request of news outlets detail the case that Sacramento County sheriff's investigators pieced together to obtain arrest and search warrants for 72-year-old Joseph DeAngelo, who is facing murder charges in multiple counties.[caption id="attachment_4492751" align="alignleft" width="380"]

Joseph DeAngelo committed at least 12 murders and over 50 rapes from 1974 to 1986. AP[/caption]DeAngelo is suspected of committing at least a dozen killings and around 50 rapes in the 1970s and '80s and the documents offer a window into the crimes that terrorized California during this period.After investigating the case for more than 40 years, police zeroed in on DeAngelo by using genealogical websites to identify potential relatives of the killer based on DNA collected at a crime scene.Investigators used DNA from a semen sample collected at the double murder of Lyman and Charlene Smith in 1980 in Ventura County to find one of DeAngelo's relatives and eventually the suspect himself, according to the warrants.After identifying DeAngelo as a suspect, investigators followed him to a store outside Sacramento and took a swab from the door handle of a car he exited. That sample did not immediately lead to an arrest, owing to the circumstances in which it was collected.The use of so-called "touch DNA" — collected when only a few human cells are left behind when someone touches an object — has raised controversy among forensic experts.Three days later, investigators collected trash from cans left outside DeAngelo's home in Citrus Heights, California. A piece of tissue plucked from the trash proved to be the piece of evidence they needed to obtain an arrest warrant, according to the documents.DeAngelo was arrested several days later and has since been charged with 12 counts of murder in California's Sacramento, Ventura, Santa Barbara and Orange counties. Investigators have searched DeAngelo's house, vehicles and storage locker, as well as his computer and cellphone. It's not clear what was recovered from DeAngelo because a judge ruled that those records should remain sealed.Authorities said the Golden State Killer stole dozens of rings, watches, cufflinks and tie pins over the years that detectives hoped to find, along with an odd assortment of items including women's purses, cameras, jewellery made from coins, china, a clock radio and a wooden bowl. He also took drivers' licenses, photographs and other identification from his victims, according to the documents.