The brutal execution of a police officer on a bone-cracking cold Missouri winter night has led to a stunning revelation: the killer is the son of a police captain, leaving a community and a police department reeling from a betrayal that hits closer to home than anyone could have imagined.
On January 11, 1991, St. Louis County Police Officer JoAnn Liscum, 38, was on midnight patrol when she spotted a suspicious man walking on Halls Ferry Road in freezing temperatures. What began as a routine welfare check turned into a cold-blooded attack that would claim her life three days later.
Liscum, a beloved field training officer known for her infectious laugh and dedication, had stopped at a convenience store before heading to investigate the pedestrian. She radioed dispatch that she was checking on a suspicious person, then went silent.
Ten minutes later, a passerby discovered a long police flashlight on the icy roadside, followed by Liscum’s body lying in the snow with a gunshot wound to her head. Her own service revolver and patrol car were missing, turning the killer into an immediate threat who could impersonate an officer.
The search for the assailant became the largest in St. Louis County Police history, with 200 officers from a dozen departments joining the manhunt. The suspect had fled on foot after abandoning Liscum’s car in a residential area, and investigators feared he would strike again.
As Liscum clung to life at Christian Northeast Hospital, her family kept a desperate vigil. She had been shot twice in the head and struck with her own flashlight. Ballistics later revealed two guns were used: her .
357 revolver and a Colt . 38.
After three days, doctors declared Liscum brain dead. She became the first officer in the department’s 35-year history to be shot to death while on patrol. Her family made the heroic decision to donate her organs, giving life to a young man who received her heart.
The manhunt intensified with a composite sketch drawn from witness descriptions of a black male in his 20s or 30s. Tips poured in, including one identifying Ralph Myers, a local with prior arrests. But that lead went cold.
Then came a bombshell from jailhouse informant Travis Stokes, who claimed he had the murder weapon. The gun was a Colt . 38, and it had been stolen from the car of a St.
Louis Metropolitan Police captain. The captain’s son, Dennis Blackman Jr. , was the prime suspect.
Blackman was under house arrest for a sexual assault charge at his parents’ home just a mile from the murder scene. Officers had actually knocked on his door the night of the shooting, but his father, the captain, said his son was home.
Investigators executed a search warrant and arrested Blackman without incident. During interrogation, Blackman claimed he had a dual personality named “Death,” who described the killing in chilling detail.
“Death” said Blackman slipped out of his parents’ house that night, carrying his father’s stolen gun. Liscum approached him, offering help. Instead of accepting, he shot her with the Colt .
38, then grabbed her service revolver and fired again. He abandoned the car and ran home.
The motive? “Death” said he wanted to destroy Dennis. “He shot at the wrong person,” the personality claimed.
“I don’t know why that idiot shot her when he was supposed to shoot me.”
Blackman was charged with first-degree murder. In a 13-day trial, the jury rejected the capital charge, convicting him of second-degree murder. He received life in prison, with an additional life term for armed criminal action.
The revelation that a fellow officer’s son had killed one of their own shattered the St. Louis police community. “We were ecstatic that we made an arrest, but it hurts that this is an officer’s son,” one detective said.
Liscum’s parents never recovered from the loss. Her mother and father, already devastated by the earlier death of their son, saw their daughter taken from them in an act of senseless violence.
The case remains a haunting reminder of the dangers officers face and the unimaginable betrayal when the killer comes from within the family of law enforcement.
