Edmund Emil Kemper III was born in Burbank, California on December 18, 1948. He was the middle child and only son born to Clarnell Elizabeth Kemper (née Stage, 1921–1973) and Edmund Emil Kemper II (1919–1985). Edmund II was a World War II veteran who, after the war, tested nuclear weapons in the Pacific Proving Grounds before returning to California, where he worked as an electrician. Clarnell often complained about Edmund II’s “menial” electrician job, and he later said “suicide missions in wartime and the atomic bomb testings were nothing compared to living with her” and that Clarnell affected him “more than three hundred and ninety-six days and nights of fighting on the front did.”

Kemper had a close relationship with his father and was devastated when his parents separated in 1957, causing him to be raised by Clarnell in Helena, Montana. He had a severely dysfunctional relationship with his mother, a neurotic, domineering alcoholic who frequently belittled, humiliated, and abused him. Clarnell often made her son sleep in a locked basement, because she feared that he would harm his sisters, regularly mocked him for his large size—he stood 6 feet 4 inches (1.93 m) by the age of 15—and derided him as “a real weirdo.” She also refused to show him affection out of fear that she would “turn him gay”, and told the young Kemper that he reminded her of his father and that no woman would ever love him. Kemper later described her as a “sick angry woman,” and it has been postulated that she suffered from borderline personality disorder.

On August 27, 1964, aged 15, Kemper was sitting at the kitchen table with his grandmother Maude Matilda Hughey Kemper (b. 1897), when they had an argument. Enraged, Kemper stormed off and retrieved a rifle that his grandfather had given him for hunting. He then re-entered the kitchen and fatally shot his grandmother in the head before firing twice more into her back. Some accounts mention that she also suffered multiple post-mortem stab wounds with a kitchen knife.

On December 18, 1969, his 21st birthday, Kemper was released on parole from Atascadero. Against the recommendations of psychiatrists at the hospital, he was released into the care of his mother Clarnell—who had remarried, taken the surname Strandberg, and then divorced again—at 609 A Ord Street, Aptos, California, a short drive from where she worked as an administrative assistant at the University of California, Santa Cruz. Kemper later demonstrated further to his psychiatrists that he was rehabilitated, and on November 29, 1972, his juvenile records were permanently expunged. The last report from his probation psychiatrists read:

Between May 1972 and April 1973, Kemper killed eight people. He would pick up female students who were hitchhiking and take them to isolated areas where he would shoot, stab, smother, or strangle them. He would then take their bodies back to his home where he decapitated them, performed irrumatio on their severed heads, had sexual intercourse with their corpses, and then dismembered them.

On May 7, 1972, Kemper was driving in Berkeley, California when he picked up two 18-year-old hitchhiking students from Fresno State University, Mary Ann Pesce and Anita Mary Luchessa, on the pretext of taking them to Stanford University. After driving for an hour, he managed to reach a secluded wooded area near Alameda, California, with which he was familiar from his work at the Highway Department, without alerting his passengers that he had changed directions from where they wanted to go. Here he handcuffed Pesce and locked Luchessa in the trunk, then stabbed and strangled Pesce to death, then killed Luchessa in a similar manner. Kemper later confessed that while handcuffing Pesce he “brushed the back of [his] hand against one of her breasts and it embarrassed [him]”, adding that he said “‘whoops, I’m sorry’ or something like that” after grazing her breast despite murdering her minutes later.

When he had saved enough money, Kemper moved out to live with a friend in Alameda, California. There, he still complained of being unable to get away from his mother because she regularly phoned him and paid him surprise visits. He often had financial difficulties, which resulted in his frequently returning to his mother’s apartment in Aptos. At a Santa Cruz beach, Kemper met a student from Turlock High School to whom he became engaged in March 1973. The engagement was broken off after Kemper’s second arrest and his fiancée’s parents requested her name not be revealed to the public.

On January 7, 1973, Kemper, who had moved back in with his mother, was driving around the Cabrillo College campus when he picked up 18-year-old student Cynthia Ann “Cindy” Schall. He drove to a wooded area and fatally shot her with a .22 caliber pistol. He then placed her body in the trunk of his car and drove to his mother’s house, where he kept her body hidden in a closet in his room overnight. When his mother left for work the next morning, he had sexual intercourse with and removed the bullet from Schall’s corpse, then dismembered and decapitated her in his mother’s bathtub.

On February 5, 1973, after a heated argument with his mother, Kemper left his house in search of possible victims. With heightened suspicion of a serial killer preying on hitchhikers in the Santa Cruz area, students were advised to only accept rides from cars with university stickers on them. Kemper had such a sticker as his mother worked at University of California, Santa Cruz. He encountered 23-year-old Rosalind Heather Thorpe and 20-year-old Alice Helen “Allison” Liu on the UCSC campus. According to Kemper, Thorpe entered his car first, who reassured Liu to also enter. He then fatally shot Thorpe and Liu with his .22 caliber pistol and wrapped their bodies in blankets.

On April 20, 1973, after coming home from a party, 52-year-old Clarnell Elizabeth Strandberg awakened her son with her arrival. While sitting in her bed reading a book, she noticed Kemper enter her room and said to him “I suppose you’re going to want to sit up all night and talk now.” Kemper replied “No, good night.” He then waited for her to fall asleep, returned to bludgeon her with a claw hammer, and slit her throat with a knife. He subsequently decapitated her and engaged in irrumatio with her severed head, then used it as a dart board. Kemper stated that he “put [her head] on a shelf and screamed at it for an hour … threw darts at it,” and, ultimately, “smashed her face in.” He also cut out her tongue and larynx and put them in the garbage disposal. However, the garbage disposal could not break down the tough vocal cords and ejected the tissue back into the sink. “That seemed appropriate,” Kemper later said: “as much as she’d bitched and screamed and yelled at me over so many years.”

Kemper was indicted on eight counts of first-degree murder on May 7, 1973. He was assigned the Chief Public Defender of Santa Cruz County, attorney Jim Jackson. Due to Kemper’s explicit and detailed confession, his counsel’s only option was to plead not guilty by reason of insanity to the charges. Kemper twice tried to commit suicide in custody. His trial went ahead on October 23, 1973.

On November 8, 1973, the six-man, six-woman jury deliberated for five hours before declaring Kemper sane and guilty on all counts. He asked for the death penalty, requesting “death by torture.” However, with a moratorium placed on capital punishment by the Supreme Court of California, he instead received seven years to life for each count, with these terms to be served concurrently, and was sentenced to the California Medical Facility.

Kemper was first eligible for parole in 1979. He was denied parole that year, as well as at parole hearings in 1980, 1981, and 1982. He subsequently waived his right to a hearing in 1985. He was denied parole at his 1988 hearing, where he said: “society is not ready in any shape or form for me. I can’t fault them for that.” He was denied parole again in 1991 and in 1994. He then waived his right to a hearing in 1997 and in 2002. He attended the next hearing, in 2007, where he was again denied parole. Prosecutor Ariadne Symons said: “We don’t care how much of a model prisoner he is because of the enormity of his crimes.” Kemper waived his right to a hearing again in 2012. He was denied parole in 2017 and is next eligible in 2024.

While imprisoned, Kemper has participated in a number of interviews, including a segment in the 1982 documentary The Killing of America, as well as an appearance in the 1984 documentary Murder: No Apparent Motive. His interviews have contributed to the understanding of the mind of serial killers. FBI profiler John Douglas described Kemper as “among the brightest” prison inmates he interviewed and capable of “rare insight for a violent criminal.”

Kemper is forthcoming about the nature of his crimes and has stated that he participated in the interviews to save others like himself from killing. At the end of his Murder: No Apparent Motive interview, he said: “There’s somebody out there that is watching this and hasn’t done that – hasn’t killed people, and wants to, and rages inside and struggles with that feeling, or is so sure they have it under control. They need to talk to somebody about it. Trust somebody enough to sit down and talk about something that isn’t a crime; thinking that way isn’t a crime. Doing it isn’t just a crime, it’s a horrible thing. It doesn’t know when to quit and it can’t be stopped easily once it starts.” He also conducted an interview with French writer Stéphane Bourgoin in 1991.

Kemper has influenced many works of film and literature. He was an inspiration for the character of Buffalo Bill in Thomas Harris’s 1988 novel The Silence of the Lambs. Like Kemper, Bill fatally shoots his grandparents as a teenager. Dean Koontz cited Kemper as an inspiration for character Edgler Vess in his 1996 novel Intensity. The character Patrick Bateman in the 2000 film American Psycho mistakenly attributes a quote by Kemper to Ed Gein, saying: “You know what Ed Gein said about women? … He said ‘When I see a pretty girl walking down the street, I think two things. One part of me wants to take her out, talk to her, be real nice and sweet and treat her right … [the other part wonders] what her head would look like on a stick’.”

A direct-to-video horror film loosely based on Kemper’s murders, titled Kemper: The CoEd Killer, was released in 2008. French author Marc Dugain published a novel, Avenue des géants (Avenue of the Giants), about Kemper in 2012. Kemper was portrayed by actor Cameron Britton in the 2017 Netflix television drama series Mindhunter. Britton received a nomination for the Primetime Emmy Award for Outstanding Guest Actor in a Drama Series because of this role.

Kemper remains among the general population in prison and is considered a model prisoner. He was in charge of scheduling other inmates’ appointments with psychiatrists and was an accomplished craftsman of ceramic cups. He was also a prolific reader of audiobooks for the blind; a 1987 Los Angeles Times article stated that he was the coordinator of the prison’s program and had personally spent over 5,000 hours narrating books with several hundred completed recordings to his name. He was retired from these positions in 2015, after he experienced a stroke and was declared medically disabled. He received his first rules violation report in 2016 for failing to provide a urine sample.

The same year he began working for the Highway Division, Kemper was hit by a car while riding a motorcycle that he had recently purchased. His arm was badly injured in the crash and he received a $15,000 (about $90,000 in 2019 when adjusted for inflation) settlement in the civil suit he filed against the car’s driver. As he was driving around in the 1969 Ford Galaxie he bought with part of his settlement money, he noticed a large number of young women hitchhiking and began storing plastic bags, knives, blankets and handcuffs in his car. He then began picking up young women and peacefully letting them go. According to Kemper, he picked up around 150 such hitchhikers before he felt homicidal sexual urges, which he called his “little zapples,” and began acting on them.