The insanity defense tends to get attention in sensational, high-profile cases: the Unabomber, Lorena Bobbitt, and most notoriously, John Hinckley. Surveys show Americans worry that too many criminals escape punishment by saying they're insane. But, in fact, successful use of the insanity defense is rare—even for defendants with profound mental illness. American RadioWorks Correspondent John Biewen examines one case that illustrates the difficulties of claiming legal insanity: the story of Kyle Zwack.

You meet Kyle Zwack in a spartan conference room with painted cinder-block walls and a noisy ceiling fan. Guards escort him in. A prison administrator stays behind, seated at the far end of the long table, to observe the interview.

Zwack is in his late 30's, pale and soft-looking in jeans, flannel shirt and glasses. He grew up in Roseville, Minnesota, a suburb of St. Paul. He now lives in a different St. Paul suburb: he's an inmate at the Minnesota State correctional facility at Oak Park Heights, the state's maximum security prison.

Ask Kyle about his background and he ticks off facts as though reading from a Cliff's Notes version of his life.

"I graduated from Kellogg [high school] in 1980," Zwack says. "Went on to the University of Minnesota, studied mechanical engineering. I became mentally ill, paranoid schizophrenic and manic depressive. I was expelled from the University and severely beaten in the Hennepin County jail by one of the deputies. After that I went out and bought a gun."

	Kyle Zwack (center) with his parents, JoAnn and Joe Zwack, at Minnesota's Oak Park Heights maximum security prison.

Zwack is articulate and lucid, though he sits in his chair without shifting and his speech is unusually flat. His parents say his anti-psychotic medication, Risperdal, is to blame for Kyle's stiff manner. But the drug also stops the hallucinations and quiets the voices that used to occupy his brain. He recalls a time, back when he'd started taking Risperdol but its effects hadn't yet taken hold: he heard a telephone ringing in his cell. "So I picked up the phone and the voice on the other side of the line said, 'Take your medication.' And I put the phone down and took my medication. Of course, I have no phone in my cell."

By all accounts, Zwack's hallucinations and delusions were in full flower on February 11th, 1986, as he drove along Interstate 10 in suburban Houston, Texas. It was the morning rushhour. A friend of Zwack's had tipped off police that Kyle was carrying weapons in violation of his parole. Lots of high-powered weapons. It's important to be armed when you're convinced the CIA, the Masons, and other shadowy forces are after you. And when you're planning to commit mass-murder back home in Minnesota.

"I was pulled over," Zwack recalls, "and I jumped out of my pick-up truck with a mini- fourteen and popped off 27 armor-piercing rounds at the police. And they fired back—seven gunmen fired on me 25 times. I took three hits, two in my bullet proof vest, one in my neck." He points out the scar on his neck left by the bullet that grazed him there. "And then I took my gun to my head and I pulled the trigger. It didn't work so I re-cocked the gun and pulled the trigger again."

The gun went click again. Failing to kill himself, Zwack begged a policeman to do it; the cop was pointing his weapon through the truck's window.

"I screamed at him to shoot me. He wouldn't shoot me. He pulled his gun away and they arrested me."

Zwack wounded one policeman in the shootout—the officer "got shot in the rear end," says the man who prosecuted Zwack, Harris County Assistant District Attorney Andy Tobias.

Never mind that Zwack only inflicted that one flesh wound, or that he clearly suffered from psychiatric problems. The young man had fired dozens of shots at Texas cops. The D.A. charged Zwack with attempted capital murder of law enforcement officers, and sought the maximum punishment.

"I asked for a life sentence, and I really thought he deserved a life sentence for what he did," Tobias says.

Zwack pleaded not guilty by reason of insanity.

The jury wasn't having it. It convicted Kyle and sentenced him to 45 years in state prison. (Though he's officially a Texas state prisoner, Zwack is doing his time in Minnesota thanks to an exchange program that allows him to be locked up close to his family.) A federal judge added 17 more years because a federal agent was present at the shootout.

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