The following episode discusses sexual assault and murder.

If you're impacted by the themes of this episode, we have resources in our show notes.

Sacramento County District Attorney Anne-Marie Schubert led a team of investigators to track down the suspect, a 72-year-old ex-police officer, arrested on Tuesday.

I thought it was crazy. I mean, you know, them finding like a guy like 40 years later. I'm pretty glad that they were able to ascertain who it was.

Turns out investigators created a genetic profile from decades-old crime scene data.

In 2018, a man with thinning white hair was pushed into a Sacramento courtroom in a wheelchair, wearing an orange prison jumpsuit.

More than 40 years after he began terrorizing communities across California in a string of rapes and murders,

Joseph James DeAngelo, the so-called Golden State Killer, had been caught at last.

DeAngelo, a 72-year-old retired cop, had committed at least 13 murders and 50 rapes throughout the 70s and 80s.

The arrest was a stunning feat, the long arm of the law reaching back through four decades to solve a seemingly unsolvable case.

And it hadn't happened through some lucky break.

DeAngelo was caught using a game-changing police technique, one that would pave the way for detectives around the world to crack open

their own murder investigations, including those that had long since gone cold.

From the Toronto Star, this is 40 years cold.

Episode two, the science. News of the Golden State Killer's arrest and the novel police technique that caught him

quickly spread through tons of media coverage.

Investigators took note.

So did families of victims, including Sean McAllen, Aaron Gilmore's brother.

You know, I just remember watching that show and being like, oh my God, this is it. This is the technology that is going to get us to the answer.

This is the golden ticket.

And I remember I called the next day and called Cold Case and I was like, hey, what about this?

And they're using it in the States.

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