People Magazine Presents: Crimes of the '90s - Who killed Theresa Wesolowski and where is he now?

Mark Libecki, the killer (Image via thecinemaholic)
Mark Libecki, the killer (Image via thecinemaholic)

People Magazine Presents: Crimes of the 90s is all set to dive into the brutal murder of Theresa Wesolowski, who was stabbed to death about a block away from her workplace. It took authorities years to solve the crime, with every lead hitting a dead end for a long time. The episode is titled 1999: Roadside Murder.

The little town of Germantown, Wisconsin, was shaken to the core when Theresa Wesolowski's co-worker found her dead body in a pool of blood on the road. The 22-year-old was allegedly stabbed over forty times all over her body and neck. Though the authorities first tried a variety of suspects, they hit a dead end in all of them. Years later, new developments in forensic studies resulted in a breakthrough.

It turned out the murderer was one of the least suspected people, Mark Libecki, a good friend of Theresa's from work. Though Libecki claimed that it was another co-worker, Tom Thompson, who killed Theresa, the authorities charged him with murder and sent him away for life. He is currently serving time at the Dodge Correctional Institution in Waupun, Wisconsin.


Theresa Wesolowski's murder: Who was Mark Libecki and what did he do?

Mark Libecki seemed like a normal guy to most people at Theresa's factory. He shared the shift with young Theresa and had a good relationship with her. He even testified that Theresa was upset on the day of her murder. Libecki was known as a quiet but likable guy who was known for showing off his daughter's pictures.

However, Libecki was far more complex than this. Unknown to his co-workers, he never had a family or a child. He lived with his parents in a mobile home in a rural part of town and had never been married. Authorities alleged that he made up this "life" to fit in with the crowd.

Theresa Wesolowski (Image via Oxygen)
Theresa Wesolowski (Image via Oxygen)

While investigating the DNA lead, authorities also discovered that he had asked another co-worker about trying his luck with Theresa. Coupled with other evidence that pointed out Libecki as the suspect, authorities theorized that Libecki asked Theresa Wesolowski out, and when she rejected him, he brutally murdered her.

He was arrested and charged with murder despite his story about another co-worker murdering Theresa Wesolowski.


Where is Mark Libecki now?

Theresa Wesolowski's killer, Mark Libecki, was charged with murder as the authorities did not believe his story about a third person being involved in the scene. He claimed that on the night of Theresa's murder, he was with another co-worker, Tom Thompson. Libecki was allegedly buying cocaine from Thompson, and Theresa Wesolowski was there with him.

Theresa allegedly got into a fight with Tom, and he ended up stabbing her. Tom also allegedly threatened Mark to keep quiet. At the time of the investigation, Tom had been dead for three years.

Authorities did not buy this story as all evidence pointed at Libecki being the killer. He was arrested ten years after Theresa's death and sentenced to life without the possibility of parole for the violent murder of the 22-year-old girl. As per prison records, he is still at the Dodge Correctional Institution in Waupun, Wisconsin.

The upcoming episode of People Magazine Presents: Crimes of the 90s will profile the case when it airs on August 12, 2022.

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Edited by Shreya Das