Kenneth Bianchi was born in Rochester, New York, in 1951, was given up at birth and adopted. He wanted to be a police officer, applied repeatedly and was rejected, and worked as a security guard. In 1976 he moved to Los Angeles and moved in with his older cousin, Angelo Buono, a car upholsterer.
Between October 1977 and February 1978 the two of them killed ten women and girls aged twelve to twenty-eight in Los Angeles. They posed as police officers, using a fake badge, to get women into their car, took them to Buono's house in Glendale, raped and tortured them, and left the bodies naked on hillsides around the city, which is where the name came from. They experimented with lethal injection, electric shock and carbon monoxide.
The ten were Yolanda Washington, nineteen; Judith Ann Miller, fifteen; Lissa Kastin, twenty-one; Jane King, twenty-eight; Delores Cepeda, twelve; Sonja Johnson, fourteen; Kristina Weckler, twenty; Lauren Wagner, eighteen; Kimberly Martin, seventeen; and Cindy Lee Hudspeth, twenty.
Bianchi moved to Bellingham, Washington, in 1979, took a security job, and in January killed two students, Karen Mandic and Diane Wilder, in a house he was supposed to be guarding. It was clumsy, he had signed for the keys, and he was arrested within days.
He then attempted an insanity defence, presenting a second personality called Steve who claimed responsibility. Several psychiatrists were convinced. Martin Orne, brought in by the prosecution, set a simple test: he told Bianchi under hypnosis that multiple personality cases usually have a third personality, and a third promptly appeared. The defence collapsed.
He pleaded guilty and testified against Buono in exchange for avoiding the death penalty, and was a poor and evasive witness. He is serving life in Washington. Buono was convicted in 1983 and died in prison in 2002. Bianchi was also excluded by DNA in 2007 as a suspect in the Alphabet murders in his home city of Rochester.