10 Criminals Who Should Have NEVER Been Released From Prison

10 Disturbed People Who Should Have NEVER Been Let Out of Prison

Welcome to WatchMojo, and today were looking at ten examples of highly disturbed and dangerous people who were voluntarily let out of prison.

Harvey Marcelin

Its not often that someone kills two people and is let out of prison both times, but thats what happened with Harvey Marcelin. Back in 1963, Marcelin was convicted of murdering an ex-girlfriend and received a life sentence. Marcelin was also continuously denied parole owing to violent and aggressive behavior in prison. However, after serving more than 21 years, Marcelin was released in May of 1984. Just one year after release, Marcelin committed a second homicide, killing Anna Miranda and disposing of her remains around Central Park. Marcelin was convicted of the crime and re-entered prison but was released yet again in August 2019. And yet again Marcelin committed murder, killing Susan Leyden in February 2022 at the age of 83.

Edmund Kemper

Even as a young man, Ed Kemper was very disturbed. Following a difficult upbringing with his mother, Kemper was sent to live with his grandparents on their California ranch. However, his mistreatment continued under them, festering further resentment. On August 27, 1964, that resentment exploded, and Kemper murdered both of his grandparents. Being just fifteen years old, he was diagnosed with paranoid schizophrenia and placed inside the maximum security Atascadero State Hospital. While not a traditional prison, Kemper remained inside until his 21st birthday in 1969. Against the advice of the hospitals psychologists, Kemper was released on parole and into the care of his mother. He would later murder his mother, along with seven others, in his famous crime spree of the 1970s.

Raymond Eugene Brown

14-year-old Raymond Eugene Brown wanted some cleats, so on October 1, 1960, he broke into the home of some relatives intending to steal money. When confronted by his aunt, he stabbed her 123 times with a kitchen knife and then murdered his grandmother and great-grandmother. Browns mother found the bodies the next day and called the police, leading to Raymonds arrest. Despite the severity of his crimes, Brown was a model prisoner and was paroled in 1973. However, this was revoked in 1980 after Brown attempted to kill his landlord. Nevertheless, he was granted parole again in 1986. Less than a year later, Brown murdered his live-in girlfriend and her young daughter. He was convicted once more and died on death row in 2008.

David Edward Maust

At just nine years old, David Edward Maust was institutionalized at his mothers request, who claimed that he exhibited dangerous behavior. Indeed. After enlisting in the Army, Maust killed teenager James McClister and was convicted of involuntary manslaughter, receiving a four-year sentence at Fort Leavenworth. He specifically asked not to be paroled, but was released in 1977. He then murdered three more people and was eventually given a 35-year sentence, but with credit for time served and good behavior, he was released in June 1999. This once again contradicted Mausts request not to be paroled. And once again, he murdered another three people after being released. Maust was finally given a life sentence, but he took his own just one month after sentencing.

Kenneth McDuff

Sometimes called The Broomstick Killer, Kenneth McDuff worked with an accomplice named Roy Green. In August 1966, Duff and Green abducted three teenagers near Fort Worth, Texas. He shot the two boys, then proceeded to sexually assault the surviving girl before strangling her with a broomstick, earning him the moniker. He was sentenced to death in 1968, but just four years later, the Supreme Court commuted many death sentences, including McDuffs, to life in prison. And then in 1989 - after serving 21 years - McDuff was released. The parole board supposedly believed that he could still contribute to society. They were wrong. Almost immediately after his release, McDuff began killing again and is believed to have murdered at least six further victims.

Jack Unterweger

In 1974, Austrian serial killer Jack Unterweger took Margaret Schäfer into the woods and killed her in a particularly brutal fashion. While in prison, Unterweger began writing an autobiography, along with poems, short stories, and articles. These writings actually garnered acclaim from Austrian literary critics and they campaigned for his release, believing that they exhibited traits of personal transformation and rehabilitation. But they misinterpreted the writings as being deep and remorseful self-reflection, when in reality they were more performative, even manipulative. But the pressure worked, and Unterweger was released on parole in 1990 after serving fifteen years. Unfortunately, he was most definitely not rehabilitated, and Unterweger murdered at least eleven more women between 1990 and 1992.

Arthur Shawcross

Professor of psychiatry Dr. Michael Stone called the case of Arthur Shawcross one of the most egregious examples of the unwarranted release of a prisoner. The story dates back to 1972, when Shawcross committed two heinous murders in Watertown, New York. Under the conditions of a highly controversial plea deal, Shawcross was sentenced to 25 years in prison with the possibility of parole. Said parole occurred just fourteen years later, when Shawcross was released in 1987. Following his release, Shawcross settled in Rochester and began a new killing spree within a year. Between 1988 and 89, Shawcross murdered at least twelve more women. He was eventually caught and sent back to prison, where he died from cardiac arrest in 2008.

Karla Homolka

Working with her then-husband Paul Bernardo, Karla Homolka committed three murders in the early 1990s. Two victims were kidnapped off the street and murdered. The third was Karlas own sister, Tammy, who they drugged and sexually assaulted. Tammy ultimately died by choking on her own vomit. Homolka then entered one of the most controversial plea deals in criminal history, dubbed The Deal with the Devil by the Canadian press. She effectively fooled prosecutors, making them believe that Bernardo was the driving force behind the crimes and that she was an unwilling participant. As a result, Homolka was convicted of manslaughter and sentenced to only twelve years in prison. She was released in 2005 and has lived free ever since.

Leslie Van Houten

One of the most famous members of The Manson Family, Leslie Van Houten was convicted for her role in the LaBianca murders, which occurred just one day after the infamous Tate killings. She was originally sentenced to death, but this was later commuted to life in prison after the California Supreme Court invalidated the states death penalty. She then served over fifty years in prison, her parole being repeatedly denied. That is, until 2023. An appeals court argued that Van Houten was no longer a danger to society, and she was released on parole at the age of 73. Her release sparked a range of reactions, from supporters who argued about the virtues of reform to opponents who were left in disbelief at her release.

Pedro López

Considered one of the most prolific serial killers in history, Pedro López murdered at least 110 people between 1969 and 1980, although he confessed to over 300. Ecuador does not impose life sentences, and in 1980, the maximum was just sixteen years. So thats what López got. However, he was considered a model prisoner and was released two years early, in 1994. Following his release, López was deported to Colombia and admitted to a mental hospital. He stayed there until 1998, when he was declared sane and released. He has led a quiet life ever since, although a number of murders that occurred in the 2000s bear similarities to his MO, leading many to believe that he continued his killing spree.

Can you think of any other shocking examples? Let us know in the comments below!