Bizarre Stabbing Incident Helped Police Crack Case Of Slain High School Cheerleader, Woman

The killer of Amie Hoffman and Dierdre O’Brien was identified after he claimed to be the victim of an attack.

November 22, 2022
Amie Hoffman [left] and Dierdre O’Brien [right] were killed by the same man in New Jersey in 1982.

The killer of Amie Hoffman and Dierdre O’Brien was identified after he claimed to be the victim of an attack.

Photo by: Warner Bros. Discovery, Inc. (Screenshot from ID's "Murder Under The Friday Night Lights")

Warner Bros. Discovery, Inc. (Screenshot from ID's "Murder Under The Friday Night Lights")

By: Aaron Rasmussen

A teenager and an adult woman in New Jersey were brutally murdered weeks apart, and authorities believe the man responsible would have become a dangerous serial killer had they not been able to stop him.

On Nov. 23, 1982, Parsippany Hills High School student Amie Hoffman, 18, worked a shift at her part-time job at the Surprise Store in the Morris County Mall in Hanover Township. When she was done, Hoffman headed to her car in the parking lot, which was isolated with no security.

“Amie’s mother became concerned when Amie did not come from work at the normal hour that she was supposed to come home,” recalled Hoffman’s fellow cheerleader and classmate, Laurelle Ivey.

Hoffman’s mother drove to the mall and found her daughter’s car. The door was open, the teenager’s purse was on the front seat and the keys were in the ignition. She immediately called the police.

On Thanksgiving, two days after the teenager disappeared, a couple walking their dog found Hoffman’s body floating in an abandoned retention tank at the Mendham Reservoir in Randolph Township. She had been sexually assaulted and stabbed multiple times, according to an autopsy.

“There was a whole new sense of fear and anxiety,” Ivey said of the atmosphere at school following her friend’s death.

Twelve days after Hoffman’s slaying, around 4 a.m. on Dec. 5, 1982, a woman in distress — later identified as Deirdre O’Brien, 25, of Mendham Township — banged on a truck driver’s door at a desolate rest stop in Allamuchy Township, New Jersey, and told him she had been stabbed and needed help.

O’Brien told the truck driver she knew she was dying and managed to describe the man she said attacked her as tall and slender with bushy hair and some facial hair. She died a short time later.

The trucker told investigators he saw a large possibly late-1960s Chevrolet leaving the rest stop. The description matched a car employees told police they saw at the mall the night Hoffman was kidnapped. Another witness also later recalled spotting a vehicle of the description on a bridge near the reservoir around 10:15 p.m. the evening of Hoffman’s abduction, The New York Times reported.

In a bizarre twist directly responsible for cracking the murder cases, shortly before midnight on Jan. 16, 1983, James J. Koedatich phoned police from his home and reported he had been the victim of a stabbing by an unknown perpetrator. According to Koedatich, a man with a flashing blue light on his vehicle pulled him over just outside of Morristown, got out of his car and then attacked him with a sharp object, leaving a puncture wound.

While emergency responders were taking Koedatich from his residence on a stretcher, a responding officer noticed a car that matched descriptions of the vehicle spotted at the mall the night of Hoffman’s disappearance and at the rest stop the morning O’Brien died.

The following day, police named Koedatich as a suspect in the cases and obtained a search warrant for the vehicle, a 1970 Chevrolet. Clothing fibers belonging to Hoffman and O’Briend were recovered from the car, police said.

Investigators looking into Koedatich’s criminal history learned he was responsible for killing two other people. He served an 11-year sentence in Florida for the strangulation death of his roommate in the 1970s. While in prison, Koedatich fatally strangled another inmate, but he claimed he acted in self-defense and was never charged.

Koedatich was released from state prison just months before he returned to New Jersey and killed Hoffman and O’Brien.

On Jan. 19, police charged Koedatich with murder. Law enforcement officials believe Koedatich was worried investigators may be on to him so he stabbed himself in an attempt to throw them off.

In October 1984, a jury convicted Koedatich for murder, kidnapping, aggravated sexual assault, and unlawful possession of a weapon with the intent to kill in connection with the Hoffman case. He was later also found guilty of kidnapping and murdering O’Brien.

Koedatich, now 73, is serving two consecutive life sentences.

“How can you ever, ever replace someone that people loved and cared about?” former Parsippany Hills Head Coach Walter Daniw said of the murders 40 years ago. “The shame of justice is that these girls are never coming back. [Do] we feel better because they got the guy? Yeah. Does it make any difference that they got the guy? Not really. Those girls are gone.”

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