MINNEAPOLIS (AP) -- A man convicted of killing a Minneapolis police officer nearly 40 years ago has left prison.

Fifty-nine-year-old Isaac Brown was released to a halfway house Tuesday after serving 37 years for shooting Richard Miller in 1981. The officer died in the line of duty just months shy of retirement.

Miller's boss, former chief Tony Bouza, says it was a ``horrible crime'' but he supports Brown's release because ``justice ought to be tempered with mercy.''

But retired officer Mike Sauro, who worked with Miller, says Brown ``murdered a police officer in cold blood'' and deserves to spend the rest of his life in prison.

The law was changed after Miller's death. Now anyone convicted of first-degree murder for killing an officer in Minnesota has no chance at parole.