A serial killer who managed to evade detection for years after brutally stabbing four women to death in random attacks has finally been identified—more than four decades later. The Denver Police Department on Friday announced that DNA had at last allowed them to crack the four related cold cases: the stabbing deaths of three women and a pregnant teenager between 1978 and 1981. The suspect has been identified as Joe Michael Ervin. He is no longer alive to face justice in a court of law, however, as police say he died by suicide in 1981 after being apprehended for the murder of an Aurora police officer who’d pulled him over for a traffic stop. “With her sacrifice, [the police officer] prevented him from killing anyone else, and it’s clear he wasn’t going to stop on his own,” said Molly Livaudais, the daughter of Ervin’s first victim, Madeleine Furey-Livaudais. Furey-Livaudais was stabbed to death by Ervin in her own home in 1978 as she prepared breakfast for her kids. Her daughters were among the surviving family members to speak at a Friday press conference about the DNA breakthrough. The other victims included 53-year-old Dolores Barajas, who was killed while walking to work in 1980; 27-year-old Gwendolyn Harris, a mother found stabbed to death on Christmas Eve that same year; and 17-year-old Antoinette Parks, who was stabbed to death in 1981 when she was between six and seven months pregnant.