This is a Sunday story, and we continue with Quill Lawrence's reporting about combat veteran Dave Carlson.

Quill first met Carlson while he was incarcerated more than 10 years ago.

At the time, Carlson was serving a prison term for a variety of crimes he'd committed after two tours in Iraq.

And a warning. this episode includes explicit language, as well as descriptions of violence and mentions of sexual assault and suicide.

Quill continues the story from here. Dave Carlson went into prison in very bad mental health.

And like we said in episode one, incarcerated veterans get very few VA services.

So his PTSD isn't being treated.

And he does not do well.

Oh, man.

At first, it was really bad.

People banging.

Like in certain areas of jail is in prison. People bang a lot. And, you know, wake up to bang, well, you know, waking up to mortars, it's waking up to bang. And then when I wake up like that, I'm in my adrenaline and it's spiked. In prison, he starts to behave like he's still at war. He reverts back into combat mode. He's coming up with tactics to keep the enemy at bay.

He came up with a whole system for cell fighting. He would put a slick of baby oil at the entrance

to his cell so anyone who rushes in would slip. And he would train specifically for cardio so he could

outlast anyone in that small space. And he's telling me, he's like, man, it was just like I was back in Iraq.

Josh Fridgen, his special forces buddy, was in touch with Carlson after he was sent to prison

and said that at one point Carlson told him he was in such a dark place that he was plotting

a kind of suicide attack from his cell.

He thought about making a shank, walking up to the guard's window,

and just slitting his throat and bleeding out in front of them just to give them PTSD.

On my calls with him from prison, Carlson told me he was having combat nightmares,

and his violent outbursts got him put in solitary for a long time.

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