Kenneth Bianchi: The Hillside Strangler Murders, Defense, and Plea Deal

Kenneth Bianchi is one of the two Hillside Stranglers, the cousins who raped and murdered ten young women and girls in the Los Angeles area between October 1977 and February 1978. He killed two more women on his own in Bellingham, Washington, in January 1979, pleaded guilty to seven murders across the two states, and is serving his sentence at the Washington State Penitentiary in Walla Walla with a projected release date of October 21, 2065. In July 2025, the California Board of Parole Hearings denied his parole for the eighth time and set his next eligibility ten years out.¹

The Los Angeles Murders

Over roughly four months, Bianchi and his older cousin Angelo Buono abducted, raped, and strangled ten females between the ages of twelve and twenty-eight. They took victims from Hollywood, Glendale, Eagle Rock, and the San Fernando Valley, and left the bodies nude on hillsides and roadsides around Glendale and Highland Park. The dumping pattern is what gave the case its name, before investigators realized two men were working together.²

The victims, in order, were Yolanda Washington, 19; Judith Miller, 15; Elissa Kastin, 21; Jane King, 28; Dolores Cepeda, 12; Sonja Johnson, 14; Kristina Weckler, 20; Lauren Wagner, 18; Kimberly Martin, 17; and Cindy Lee Hudspeth, 20.³ All bore ligature marks on the neck, wrists, and ankles, and all showed signs of sexual assault.² By Bianchi’s own later account, nine of the ten killings took place at Buono’s upholstery shop and residence at 703 East Colorado Street in Glendale.

The Bellingham Murders and How He Was Caught

The break in the case came from Washington, not California. Bianchi had moved to Bellingham and was working part-time for a security company. On January 11, 1979, he lured two Western Washington University students, Karen Mandic and Diane Wilder, to a house he was supposed to be watching. He tied them up, sexually assaulted them, and strangled them. Their bodies were found the next afternoon in the backseat of a car in the Edgemoor neighborhood.⁴

Forensic evidence tied him to the killings quickly. The FBI recovered fibers from the victims’ clothing inside the house he had been monitoring, found his pubic hair on one victim’s outer clothing, and identified semen stains on both victims’ clothing.⁵ When Bellingham police called the Los Angeles County Sheriff’s Department about their suspect, L.A. detectives recognized that the addresses on his California driver’s license and his former Glendale residence matched locations connected to the Hillside Strangler abductions. That call finally linked the two crime sprees.⁶

The Fake Multiple Personality Defense

After his arrest, Bianchi tried to claim insanity. His defense attorney arranged for psychologist John Watkins to hypnotize him during a competency evaluation, and under hypnosis Bianchi produced a personality called “Steve Walker” who confessed to the murders. Several mental health professionals initially believed the presentation.⁷

Prosecutors brought in Dr. Martin Orne, a hypnosis expert from the University of Pennsylvania. Orne told Bianchi that most people with multiple personalities have more than two, and on cue Bianchi produced a third one named “Billy.” Orne then ran what he called the double hallucination test. He told the hypnotized Bianchi to visualize his attorney, Dean Brett, sitting in a chair. When the real Brett walked in, Bianchi expressed confusion about how the lawyer could be in two places at once. A genuinely hypnotized subject, Orne concluded, would have accepted both presences without difficulty.⁸

Investigators then found where the alter’s name had come from. “Steve Walker” was a real psychologist whose identity Bianchi had stolen to set up a fraudulent psychiatric practice in Los Angeles. He had placed a classified ad in the Los Angeles Times under the fake name “Dr. R. Johnson,” soliciting resumes and transcripts from recently graduated psychologists, and used the responses to forge diplomas in his own name and talk his way into borrowing a legitimate psychologist’s office. Once detectives traced the ad, the claim of a spontaneous alter personality collapsed.⁷ Experts ultimately diagnosed him with antisocial personality disorder with sexual sadism.

The Plea Deal

With the insanity defense gone, Bianchi entered a plea agreement with both states in October 1979. In Washington, he pleaded guilty to two counts of first-degree murder for Mandic and Wilder and received two consecutive life sentences after the state withdrew its request for the death penalty. In California, he pleaded guilty to five counts of first-degree murder, one count of sodomy, and one count of conspiracy to commit murder, kidnapping, or rape, and received concurrent life sentences.⁵

The condition attached to the deal was that Bianchi would testify truthfully against Buono, who faced ten counts of murder in California. As an incentive, California agreed he could serve his time there first, where treatment programs were better. California authorities later concluded he had failed to cooperate fully and sent him back to Washington to serve his sentences there instead.⁵

Buono’s Trial

The case against Buono nearly fell apart. In 1981, Los Angeles District Attorney John Van de Kamp moved to dismiss all murder charges, calling Bianchi “devoid of credibility” because he had changed his story repeatedly.⁶ Superior Court Judge Ronald George refused the dismissal, ruling there was enough evidence to try the case.⁹ Van de Kamp declared a conflict of interest, and Attorney General George Deukmejian’s office took over.

The trial that followed was the longest murder trial in American history to that point. Jury selection began in November 1981, and proceedings ran 729 days with 392 witnesses and 1,807 exhibits. In November 1983, Buono was convicted on nine of ten counts and sentenced to life in prison without the possibility of parole.⁶¹⁰¹¹

Where Kenneth Bianchi Is Now

Bianchi is held at the Washington State Penitentiary in Walla Walla. His Washington sentence, originally two consecutive life terms, was recalculated in 1990 to more than 118 years following changes in state law, with a projected release date of October 21, 2065, when he would be over 110 years old.¹²¹³¹⁴

He is no longer legally named Kenneth Bianchi. On November 5, 2023, he changed his name to Anthony D’Amato, an alias he had used for years and had first tried to adopt formally in 1984. He told officials he wanted to become a “lesser-known inmate.” The change came shortly after renewed attention from the four-part Peacock docuseries The Hillside Strangler: Devil in Disguise, which premiered in August 2022.¹⁵

Since 1990, he has filed numerous petitions in Washington’s appellate courts and one federal habeas petition, arguing that his 1979 confession was the product of hypnotic manipulation and that forensic evidence against him was fabricated. No court has granted relief. Washington’s Indeterminate Sentence Review Board classifies him as a level III sex offender, and evaluators have found he meets the criteria for psychopathy and has shown no genuine rehabilitation or remorse.⁵

1
Los Angeles Times. Hillside Strangler, a Convicted Serial Killer, Gets Denied Parole
2
Loyola of Los Angeles Law Review. Hillside Strangler Murders, Legal Analysis
3
Biography.com. Kenneth Bianchi
4
Bellingham Herald. Kenneth Bianchi Bellingham Murders
5
Washington Courts. In re Personal Restraint of Bianchi, No. 82123-7-I
6
Los Angeles Times. Crimes of the Times: The Hillside Stranglers
7
University of Pennsylvania. Orne et al., Hypnotically Induced Testimony
8
TIME. Behavior: Was It Hypnosis or Hype
9
United Press International. State to Prosecute Hillside Strangler Suspect
10
Los Angeles Times. Angelo Buono Dies in Prison
11
Washington Post. Angelo Buono Jr. Dies at 67
12
Washington State Standard. WA Board to Consider Parole for Hillside Strangler
13
CBS News. Hillside Strangler Kenneth Bianchi Denied Parole
14
California Department of Corrections and Rehabilitation. Board of Parole Hearings, Week of July 7–11, 2025
15
Democrat and Chronicle. Hillside Strangler Kenneth Bianchi, Rochester NY Native, Changes Name in Prison