I'm Lester Holt, tonight on Dateline.

I wonder why I didn't do more.

I should have done something different.

I'll live with that, forever.

Forever and ever it will haunt me.

There's a fire and my wife is... His wife was inside.

She was lying on her left side, like she was under the covers, asleep.

I was a little shocked.

There was no soot in her airway or in her lungs.

The neighbor, she believed she heard what was a gunshot.

In the front driver's seat was what appeared to be a note. I don't care what you think

you're saying. You're dealing with a murder. Did you order her? No. Did you pull the trigger?

No. Did you kill her? No. It was like a script. He had answers for everything. I left that courtroom

100% convinced that he didn't do it.

No one wants to send an innocent person to prison.

You want the truth.

You're going to hell for what you've done in this case.

... Here's Keith Morrison with burning suspicion.

It was dark past 3 a.m.

A weak hint of crescent moon struggled to penetrate the night here in the middle of America.

Kingman, Kansas, population 3,000, was asleep.

Except, on a quiet residential street, a woman unable to sleep watched a crime show on TV.

...