This is Hidden Killers with Tony Bruske. Here now, Tony Bruske.

There's something especially disturbing about a murder case that hinges not on DNA, not on

surveillance footage, not on a smoking gun, but a chain of assumptions. The state of Utah

versus Corey Richens has always been one of those cases from the

very beginning. Prosecutors told the public that Corey, a real estate agent, and mother of three,

Marr... unalived. Her husband, Eric Richens, by slipping a fatal dose of fentanyl into his drink.

But they didn't say that they had the fentanyl. They didn't say they had the pills or the

confession or a witness who saw the act.

What they had was a theory and a theory just got punched in the face by their own witness.

Let's start there, shall we?

Wait a second, Tony, this sounds different than most of the story you've talked about.

Yeah, it does.

It does because things change. People change. Things move around.

So it's always good to keep an open mind and roll with the punches. I don't know where I'm

rolling in this story yet, but let's roll together and see where we land.

In October 25, Corey's defense team filed two blistering motions, one to reconsider bail and another to compel.

What they see is exculpatory evidence the prosecution has been sitting on for months.

At the center of this procedural earthquake is a man named Robert Krazer,

who the state previously identified as the supplier of the fentanyl used in the unaliving.

I hate using that word, but I'd like you to see the video.

According to the state, Krozer sold the drugs to Corey's housekeeper,

Carmen Lauber, who then passed them along to Corey.

...