CHICAGO (STMW) — A convicted murderer who took the lead in a federal lawsuit claiming a “sadistic culture of brutality and violence” in the Cook County Jail has been charged with threatening to shoot up a Chicago Police officer’s North Side home if she testified against him.

Tylon Hudson, 41, who was convicted of a 2007 murder last month following a bench trial, allegedly sent the letter in July, which threatened to harm her and “shoot” her “crib” up, according to a police report.

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“Eventuall[y] we a get you if you come to Markham courthouse in room 107 and lie this week,” the letter said.

Hudson is charged with aggravated intimidation of a peace officer and unlawful communication with a witness.

Police linked Hudson to the letter through his fingerprints, despite his attempts to conceal his identity, police said. An alternate name and address were listed on the letter.

The cop who received the letter at her home immediately called police. She is an officer assigned to the Fugitive Apprehension Section, authorities said.

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Hudson was convicted of murder and unlawfully possessing a firearm as a felon on Aug. 1. He has filed a motion for a new trial and will appear in a Markham courtroom on Sept. 17, court records show.

Hudson is the lead plaintiff in a class action civil rights federal lawsuit filed this year, on behalf of 200 maximum security inmates, alleging violence and brutality at the jail, including allegations that officers slammed inmates to the floor and kicked and punched them while they were handcuffed and shackled.

Cook County Sheriff Tom Dart, Cook County Board President Toni Preckwinkle and top jail administrators were named in the federal suit filed in February.

Dart in February questioned Hudson’s credibility, who had eight of his 10 lawsuits against the county thrown out and is the only plaintiff seeking monetary relief.

Hudson was ordered held without bond Wednesday for the latest charges.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)