A Convicted Felon Found Dead in Cook County Jail
Marvin Flanagan, a nine-time convicted felon, was found hanging in the Cook County jail just two days after being found guilty of escaping electronic monitoring and killing a man. Flanagan, 33, was pronounced dead on December 20 after correctional staff discovered him hanging in a jailhouse shower in what appeared to be a suicide attempt, according to the Cook County Sheriff’s Office.
Judge Joanne Rosado had found Flanagan guilty of four murder counts on December 11, according to court records. She dismissed the murder case last week, along with six pending cases involving allegations that Flanagan battered correctional officers while awaiting trial for the murder.
Flanagan was convicted of killing 39-year-old Miguel Perez during a December 21, 2020, home invasion in Humboldt Park. At the time of the murder, Flanagan was supposed to be home on electronic monitoring for an armed habitual criminal gun charge.
According to prosecutors, Perez was socializing with friends in his basement apartment when his home security system detected movement near the alley and sent an alert to his phone. Armed with a handgun, Perez went outside to investigate and was shot almost immediately after walking out the door. Perez reportedly fired several shots before losing consciousness.
Shortly after police arrived at the scene, St. Mary’s Hospital notified CPD that a man had arrived at their emergency room with gunshot wounds, prosecutors said. That man was Flanagan. Security footage showed a silver SUV pulling up to the hospital around 3:05 a.m. and the driver dumping Flanagan from the back seat, prosecutors said. Blood found on a fence, a car, and pavement near Perez’s home all matched Flanagan, prosecutors said.
Prosecutors said someone at the gathering sent Flanagan a message indicating Perez was wearing “chains and jewelry,” suggesting robbery as the motive for the attack. Prosecutors also said Flanagan made incriminating statements about Perez’s murder in recorded jailhouse phone calls.
Two days after Rosado convicted Flanagan, Cook County correctional staff found him hanging from a shower in the jail’s Residential Treatment Unit, according to a Sheriff’s Office spokesperson.
“Correctional deputies and Cermak Health Services medical staff immediately began life-saving measures, including CPR and an automatic external defibrillator, and called 911,” the spokesperson said. Flanagan died a week later at Mt. Sinai Hospital.
“While Flanagan’s death appears to be a suicide, the official cause of death will be determined by the Cook County Medical Examiner’s Office,” the spokesperson said. “The Sheriff’s Office has also requested an independent investigation by the Illinois State Police Public Integrity Task Force.”
“Flanagan was originally booked into Cook County Jail on October 8, 2019, for a gun charge and was subsequently indicted on charges of armed habitual criminal and felon in possession of a firearm,” the spokesperson explained. “In July 2020, the judge in this case reduced his bond and ordered electronic monitoring as a condition of release. In September 2020, bond was posted for Flanagan, and he was released on electronic monitoring.”
The spokesperson said Flanagan was declared AWOL from electronic monitoring in October 2020, two months before the murder, and he remained at large until they found him at Stroger Hospital, where he had been transferred for treatment of the gunshot wounds he suffered while murdering Perez.
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