03/27/2012 08:41 pm ET

Lamar Cooper, Chicago Man, Sentenced To Life In Prison For Killing Police Officer

A 40-year-old Chicago man was sentenced Tuesday to life in prison with no chance of parole in the 2008 shooting death of Nathaniel Taylor Jr., a Chicago police officer.

Lamar Cooper was convicted in January of first-degree murder in the slaying of Taylor. Though Cooper's attorney argued that his client was acting in self-defense, a jury did not believe those claims, the Associated Press reports.

"I hope you live a long long life behind bars so you can remember what you did for the rest of your life," Cook County Judge Nicholas Ford told Cooper Tuesday, according to the Chicago Sun-Times.

The Chicago Tribune reports that Cooper fatally shot Taylor as he was executing a search warrant for Cooper's home. As Taylor approached Cooper's car in the city's South Chicago neighborhood on Sept. 28, 2008, Cooper gunned the officer down.

Lem Miller, Taylor's partner, fired 10 times at Cooper, hitting him nine times before he called for help, CBS Chicago reports. Taylor, 39, a 14-year police veteran, died hours later at the Advocate Christ Medical Center in Oak Lawn.

"We had a hero here whose life was taken from us way too soon," Cook County State's Attorney Anita Alvarez said of Taylor's death in January, Fox Chicago reported.

Cooper, a known drug dealer and convicted felon who previously served jail time after being convicted of the attempted murder of a police officer, claimed he did not realize the Taylor was a plainclothes police officer and thought he was being robbed, according to the Tribune.

Miller testified in court that Taylor identified himself as a police officer before Cooper opened fire, CBS reports.

Cooper was also convicted of three counts of drug possession for controlled substances found inside his house, according to NBC Chicago.

WATCH a previous report on Cooper's conviction: