MINNEAPOLIS (AP) — A man convicted of killing a Minneapolis police officer in 1981 will be released to a halfway house next week after spending nearly 37 years in prison.

Isaac Brown, 59, will wear a GPS monitor when he is released July 10 and the Minnesota Department of Corrections said he will be closely monitored. But his impending release has upset the officer's widow, who said she thought Brown would never be freed.

"When they said 'life,' I thought they meant life and I thought there'd be no question to it," Lea Miller, 89, told KMSP-TV .

Brown shot officer Richard Miller three times in the chest after Brown got out of a stolen car. Miller was months away from retirement.

Brown became the first person convicted under a state law that required life sentences for killing a police officer. But the sentence included the possibility of parole. Lawmakers modified the law a year after Miller's killing to remove the possibility of parole.

Lea Miller said her husband "loved being a policeman."

"He loved going to work when he was working the night shift," she said. "I could hear him whistling on his way to work, just a good soul."

Brown went before the parole board six times before he was granted release to a halfway house in April.