So it's huge insight for the homicide investigators who up to that point were just chasing a ghost.

Traits of a sexual sadist, we know that these women suffered.

Enditements of very famous soccer players and the jury did not believe the woman.

Hello and welcome to Best Case Worst Case. This is your host Jim Clemente, former New York City prosecutor, retired FBI profiler and writer producer on CBS's Criminal Minds.

And with me today in the studio is...

Hi everybody, it's Francie Hakes, former state and federal prosecutor. How are you Jim?

I'm great. I'm really happy to be here again live at CrimeCon.

With our very special guest, I'm Paul Holes, retired co-case detective from Contra Coss County DA's office.

I have a quick question. Can you guys come back to LA with us and do this all the time?

We love this. So we've been talking to detective Paul Holes about a very interesting co-case that he worked.

And this case has now jumped from jurisdiction up north in California down to southern California.

What did you think when you found out that this offender was actually physically with the N.A. scientifically tied to southern California now?

And there's an escalation.

Very much this was an escalation. That was an evolution where you see this guy that is doing the sexual assaults in northern California.

And towards the end of his northern California series, the female victims were starting to say he's not getting what he needs.

So there was a sense...

Wait, wait, wait, what do you mean by that? What did they mean by that?

So what they were meaning is, is during the sexual assault they were sensing that this guy just wasn't getting satisfied.

And they thought that he wanted more out of it. And then when he shows up in southern California and he's making the statement,

I'm going to kill him. I'm going to kill him this time in the very first attack down there. In his mind, he is recognizing he needs to do more.

He is escalating psychologically. And we saw that. Now we had tied the DNA between northern California and southern California. Now we know he did escalate to homicide.

Right. And so when we look at this from a profiling perspective or a behavioral perspective, typically we see this kind of escalation happen in serial rape cases when the offender is almost caught.

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