Matthew Steven Johnson was born on May 24, 1963, in Hartford, Connecticut. He was one of ten siblings and a twin. He grew up in the Blue Hills and Asylum Hill neighborhoods of Hartford. When he was 12 years old, he lost sight in one eye due to an accident involving a pellet gun. People who knew him as a child described him as a sweet boy, but he also showed immature behavior. For example, he would suck his thumb when he did not want to do something. His kindergarten teacher noted that he could be very aggressive and had trouble coping with being told no.

As he grew older, Johnson faced many challenges. By his teenage years, he had been admitted several times to the Connecticut Children's Medical Center for evaluations. He had a limited academic ability, which was attributed to an intellectual disability. Johnson showed talent in music and physical education, but he also had health issues, including seizures that required medication. His recorded IQ was 69.

At 17, Johnson had little contact with his father but visited his family on weekends. He became tired of the evaluations and stopped taking his medication, saying it made him feel dizzy. During this period, he reportedly became depressed. To cope with his feelings, he started mixing drugs and alcohol. Despite these struggles, he sought help at The Institute of Living in Hartford. While there, he earned his high school equivalency diploma before beginning work as a laborer.

At the age of 19, Matthew Steven Johnson attempted to kill a security guard during a robbery at the Cathedral of St. Joseph. He was sentenced to ten years in prison but only served four years. Before this incident, in May 1980, he robbed and assaulted a pregnant woman. Later in 1988, Johnson forcefully restrained another woman on the street. About two years after that, he raped and beat yet another victim. Both women were able to identify him, leading to his arrest.

After Johnson was released from prison, he became homeless. He started luring drug-addicted sex workers to secluded areas in Hartford. Once there, he would have sexual encounters with them, then strangle them. After strangling his victims, he would brutally stomp on them, crushing their necks and skulls.

Johnson murdered three women:

1. Aida Quinones, who was 33 years old at the time of her death in April 2000.

2. Rosali Jimenez, also 33, was killed in August 2000.

3. Alesia Ford, who was 37, was murdered in July 2001.

Johnson is also suspected of being involved in the deaths of two other women, though he has not been charged in their cases:

1. LaDawn Roberts, 28 years old, was found dead on a back porch in June 1999.

2. Rosalind A. Casey, 32, was discovered dead in June 2000.

In January 2002, authorities arrested Johnson after forensic scientist Henry Lee linked the deaths through DNA testing. Samples from the crime scenes matched Johnson’s DNA. During his trial, the brother of one victim urged the jury to give Johnson the maximum sentence. Although Johnson expressed sympathy for the victims’ families, he did not admit to his crimes. When the jury announced their verdict, Johnson showed no reaction.

Connecticut law provided for a maximum penalty of 60 years for each murder count. Johnson was sentenced to 60 years for each of the three murders, totaling 180 years in prison. In 2008, the Connecticut Supreme Court upheld this verdict. Johnson argued that he should have had separate trials for each murder and claimed he had not had sexual contact with a woman since 1982, which he believed explained his DNA being found at the crime scenes.