Home » The Hillside Stranglers: Cousins Turned Killers

The Hillside Stranglers: Cousins Turned Killers

The Hillside Stranglers

In 1979, cousins Kenneth Bianchi and Angelo Buono were arrested as the main suspects in the kidnapping, rape, torture, and murder of ten female victims whose ages ranged from twelve to twenty-eight years old.  Upon their capture, police uncovered a pair of close relatives who had become a rarely-seen serial killer team.

While they only worked together for a year, they viciously brutalized their victims. Bianchi and Buono would commit sadistic acts like burning their victims, as well as injecting them with Windex, and even dumping a victim’s corpse in her own car before pushing it off a cliff. However, before these two joined up to commit these horrendous feats, they each had backgrounds that set them on the path to being deviants.

Kenneth was abandoned at birth by his alcoholic, prostitute mother, and was adopted by the Bianchi family, but he had a troubled childhood. He struggled with wetting the bed until he was a teenager, had trouble sleeping sleeping, and was a compulsive liar. Bianchi was described by those who knew him as a ‘born loser.’ He was also easy to influence, being susceptible to whomever was perceived to be in the power position of relationships, groups of friends, etc.

Reportedly, in 1957, when he was six years old, he fell off the jungle gym at a playground, leaving him with a substantial head injury. Many sources mention this as a tip of the hat to the possibility that Bianchi may have had a frontal lobe injury that would have altered his personality in a negative way, sharing with the likes of Gacy and Bundy, who suffered similarly.

Angelo Buono, the older of the two, on the other hand, was troubled from day one, being abnormally obsessed with sex from a young age. His childhood and teen years were plagued by a lengthy criminal record, lewd sexual acts (like pulling down girl’s underpants), and bragging about supposed rapes he had committed at age 14.

Buono married his high school sweetheart, but soon abandoned her and the child they had together. Domestic violence issues then appeared with his second wife, Mary Castillo. Mary was repeatedly abused by Buono and it was reported that he raped their two year old daughter before Mary finally left him. However, after she left, Mary decided to try and fix the marriage, but was met with being handcuffed and held at gunpoint by Buono, so she (understandably) abandoned the idea. Nannette Campion was his third wife, who also left him after he abused her and raped Campion’s daughter from a previous marriage.

As an adult, Bianchi already had one failed marriage, so he decided to go to college for psychology, but dropped out after one semester. After leaving, he set his sights on joining the police. Bianchi had a lifelong obsession with becoming a cop and it was his dream to have a badge. Like many killers who apply for law enforcement, Bianchi was constantly rejected by the police, for unknown reasons, but more than likely it was because he failed psych tests.

The Hillside Strangers 2

This second major rejection was followed by a cycle of Bianchi getting jobs and then losing them because he was constantly stealing money from his employers and giving the stolen goods to girls he was dating. By the time Bianchi lived with Buono, he had already faced a life that did not include a wife, children, career, or any remote signal of success. This, combined with Bianchi’s easily influenced personality and his desire for power and success, made him ripe for Buono to use and manipulate.

While Buono is the obvious aggressor in the team, Bianchi was a willing partner who was attempting to overcome his lifelong rejection from the people and organizations he loved. Additionally, Buono’s already burning hatred of women was an easy high to ride and Bianchi just joined up, participating for his own reasons. Initially, Buono taught Bianchi to coerce sex from women, but then they moved to pimping out young girls for money, which failed and led them to murder their first prostitute.

While humiliating these women by raping them was more Buono’s game, it also served a dual purpose that rewarded Bianchi.  According to Psychology Today, “To humiliate someone is to assert power over him by denying and destroying (his/her) status claims.” So, basically, while Buono was relishing in the act of rape and escalating to murder, Bianchi was relishing in the power it brought him. Since their victims were so young they were more than likely chosen to accentuate the fact that these grown men, who were their fathers’ age, were stripping them of their identity by the heinous acts of rape and murder.

After a year, Buono decided to stop killing in the wake of increased police suspicion. Bianchi moved to Bellingham, Washington to join his girlfriend who had just given birth to their son. Interestingly enough, Buono defied serial killer behavior and appeared to stop murdering as soon as Bianchi left. Bianchi however could not stop and used his position as a security guard at Western Washington University to lure two young women, 22-year-old Karen Mandic and 27-year-old Diane Wilder, to a house he was hired to guard while the owners were away.

He had one of the women descend the staircase to the basement in front of him and then strangled her from behind. Bianchi then called for the other girl, to repeat the act.  However, without Buono, who apparently was the better of the two at cleaning up after them, Bianchi left many clues behind that subsequently led to his capture. Apparently, one of the women also told her boyfriend who they were going out with, so once she was missing, Bianchi became the prime suspect.

When Bianchi was arrested for the Washington murders, he was connected to some of the Hillside Strangler crimes and at trial claimed the insanity defense, proclaiming that he suffered from multiple personality disorder. There are really weird tapes of these supposed interviews the defense prepared of him being ‘hypnotized’ so the multiple personalities could be addressed on camera. These supposed recorded events of his multiple personality disorder are very strange and there is something off about them, that you really be put into words.

The prosecution had a similar feeling of unease at these taped sessions and hired a renowned psychiatrist who specialized in hypnosis and quickly disproved Bianchi’s ‘disorder’, getting him to admit that he was faking it. Instead of multiple personality disorder he was diagnosed as suffering from antisocial personality disorder with sexual sadism effects (this is common in a lot of serial killers).

The Hillside Strangers 3

He almost immediately confessed to his crimes and took a plea deal of life in prison, but part of the agreement involved him being the star witness at Buono’s trial. In order to complete a plea deal of this nature, it is common practice to confess your crimes in full witness of the court and a judge. During his confession, Bianchi evidently cried and said he was sorry, but after he left the presence of the court he was seen laughing and joking in the hallway with his lawyer.

He was apparently a nightmare of a witness at Buono’s trial and was on the stand for six months straight. Often he would cooperate with the prosecutor and agree with the facts presented, but sometimes he would get obstinate and contradict himself. Apparently, he was trying to not be the sole cause of Buono’s demise, but it didn’t matter since Buono received life in prison anyway. Law Enforcement and members of the court recount groan-worthy interactions with Bianchi because he was such a pain in the ass.

Bianchi is currently serving his sentence at Washington State Penitentiary in Walla Walla and is 65 years of age at the time of writing.  He was denied parole on August 18, 2010 by a state board and will be eligible to apply again in 2025. Buono died in his cell, alone, of a heart attack in 2002 after being incarcerated for over twenty years.

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Written by Syl
Syl is a professional criminologist who shamelessly spends her time listening to true crime podcasts, watching horror films, and bringing real life horror to her written pieces.
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