Killer eludes police for 31 years – how did one woman find him in two hours?

When Chelsea Rustad uploaded her DNA on a public database, she never expected two police investigators would appear on her doorstep. GAYLE KING | "CBS THIS MORNING": Investigators in California say DNA evidence led them to one of the country's most notorious serial killers. …He is believed to be the so-called Golden State Killer. TALBOTT'S SISTER: He was really an angry kid. TALBOTT'S OTHER SISTER: Yeah, he … could be a bonehead, but not to the point of … attacking or killing somebody, no. LAURA BAANSTRA: It's hard to put into words this feeling of relief, of joy, of -- of great sorrow that this arrest brings. LEONA COOK: On one hand, we are close to closure, and on the other, we're still at a loss and I don't have my only son, Jay. DET. JIM SCHARF: If it hadn't been for genetic genealogy we wouldn't be standing here today. RACHEL FORDE: They never stopped to consider that perhaps the person who left the DNA was not the murderer. MATTHEW BALDOCK: He had zip ties. He had gloves. He had a firearm. He had ammunition.  "We the jury find the defendant William Earl Talbott II guilty of the crime of murder." CHELSEA RUSTAD: John? CHELSEA RUSTAD [hands John a bouquet]: I wanted to give this on behalf of the Rustad family. LEONA COOK: Some of us wanted a shirt or a sweater. You wear them. You could put them to your nose and smell him. I still have that old sweater in my dresser drawer. Thank you. JUDGE: The court's only possible sentence for each count is to impose a sentence of life without the possibility of release.

"They let me know that they are investigating a family member of mine for murder," she tells "48 Hours" correspondent Erin Moriarty. "… a double homicide from 1987 … This was a person who was in my family tree." TALBOTT'S SISTER: He beat me up, broke my tailbone, I had to go to the hospital. JOHN VAN CUYLENBORG: Chelsea? JOHN VAN CUYLENBORG: Wow, that's very thoughtful. Thank you for coming today.

For more than 30 years, investigators in Washington state had been trying to solve the murders of 18-year-old Tanya Van Cuylenborg and her 20-year-old boyfriend, Jay Cook. CHELSEA RUSTAD: Pleasure to meet you.