Two brothers accused of killing a lawman who was tracking them after a robbery say they feared police would kill them because of their unpunished assistance to spy Christopher Boyce.

"Once they figured out who we were, with our connections with the Boyce deal and all, they weren't going to bring us back alive," Joe Pratt told The Spokesman-Review, a Spokane, Wash., newspaper.Joe and his brother Jim are accused of robbing a Sagle, Idaho, home Jan. 11, briefly taking a hostage and shooting at a police detective's car the same night. The detective was not hurt.

The brothers are charged with first-degree murder in the next day's shooting death of U.S. Forest Service law enforcement officer Brent Jacobson, a Provo, Utah, native and a member of a posse that tracked the Pratts until their surrender a few hours after Jacobson was killed.

"This is a mess. It's just a mess," said Joe Pratt, 27, who along with his brother is lodged at the Bonner County Jail. "It just got out of control. No one was supposed to be hurt."

Jim and Joe Pratt, along with their brother Kendall Brett Pratt, 33, gained notoriety in 1982 for helping and then betraying Boyce.

The brothers were granted immunity from prosecution and each paid $25,000 for testifying about bank robberies they and Boyce pulled off in Washington, Idaho and Montana after Boyce escaped a California federal prison, where he was serving time for selling secrets to the Soviets.

Jim Pratt, 29, said that during the 22-hour manhunt through snowy woods for he and his brother, "We felt like chased animals."

"You don't have much of a choice but to run. We had no doubt they would shoot to kill," he said.

After running through deep snow throughout the night and most of the next day, Jim Pratt said he and his brother stopped under a tree to sleep.

"That's when the deputy and the Forest Service guy came up on us," Jim Pratt said. "They surprised us. The deputy said, `Drop your weapons.' I told him to drop his weapons.

"I was about to say I don't want to get shot, when he fired," Jim Pratt said. "It sounded like a thud. Then all of a sudden I felt this burning, and I fired back. I didn't know any of them had been shot. I'm still not sure I shot him."

Jim Pratt, who was shot in the leg, was carrying the short-barreled shotgun police say was the weapon that killed Jacobson, the first U.S. Forest Service officer to die in the line of duty.

"The whole thing is just like the Boyce deal, it just got bigger and bigger," Jim Pratt said.

Prosecutors say they will seek the death penalty if the brothers are convicted.

"I'm worried about going to prison," Joe Pratt said. "A snitch is just about the worst thing to be in prison."