True Crime in the Great Outdoors

The most shocking crimes from national parks, camping trips, backpacker murders, and hiking incidents

StrangeOutdoors.com 11/27/20 StrangeOutdoors.com 11/27/20

The frightening case of the Trailside Killer David Carpenter

David Joseph Carpenter, The “Trailside Killer” murders 1979-1981, cALIfornia

Revised October 2023

David Joseph Carpenter, also known as the “Trailside Killer”, spent the years from 1979 to 1981 preying on hikers and nature walkers in and around Northern California’s outdoor spaces. The Santa Cruz Mountains and Marin County beauty spots like Point Reyes National Seashore, a vast expanse of protected coastline in Northern California, were Carpenter’s favorite hunting grounds for victims.

Carpenter killed ten people and possibly several more, with two survivors from his attacks, Steven Haertle and Lois Rinna, the mother of The Real Housewives of Beverly Hills star Lisa Rinna.

Criminologists have described Carpenter as having a Dr Jekyll and Mr Hyde character - sometimes the amenable, bumbling, stuttering Mr Nice Guy. The next is an evil, sadistic hunter of women in the wilderness, ready to impart unspeakable violence.

"From the crimes, detectives concluded that the killer enjoyed making a ritual out of the killings, inflicting psychological torture on the victims, and as Marin County Sheriff Al Howenstein put it, 'putting the victims at some point in a position of pleading for their lives,'" wrote the Los Angeles Times.

Early life of David Carpenter

David Carpenter was born in San Francisco on May 6, 1930. He was physically abused as a child by his alcoholic father, Elwood, and domineering mother, Frances. Between the ages of 3 and 11 years, David had a severe stutter and a persistent bed-wetting problem and enjoyed being cruel to animals.

The Macdonald triad (also known as the triad of sociopathy or the homicidal triad) is a set of three factors that have been suggested if any combination of two or more are present together, to be predictive of, or associated with, a later violent tendency, particularly with relation to serial offenses. The triad was first proposed by psychiatrist J. M. Macdonald in "The Threat to Kill", a 1963 article in the American Journal of Psychiatry. However, although it remains an influential and widely taught theory, subsequent research has generally not validated this line of thinking.

The triad links cruelty to animals, obsession with fire-setting, and persistent bedwetting past a certain age to violent behaviours, particularly homicidal and sexually predatory behaviour. Further studies have suggested that these factors are more linked to the childhood experience of parental neglect, brutality or abuse. Some argue this, in turn, results in "homicidal proneness".

Carpenter was forced to take ballet and violin lessons as a child and tended to dress in garish clothes. This, together with the stutter, meant he was a target for bullying at school.

At age 14, Carpenter was sentenced to California’s Napa State Hospital for undisclosed sex offenses. Three years later, he was sentenced to the California Youth Authority after he was caught molesting his cousins, who were 3 and 8 years old.

Following his release, Carpenter lived what appeared to be an ordinary life. In 1955, the 25-year-old man married 19-year-old Ellen Heattle. The couple had three children together—Michael David (born 1956), Gabrielle Louise (born 1958), and Circe Anne (born 1960).

Despite having three children, the couple’s marriage was far from ordinary. Ellen later told authorities that her husband was a sex addict who demanded intercourse at least three times a night.

The Trailside Killer’s crimes

Carpenter was linked to many serious crimes and, at one time, was even connected to the infamous Zodiac Killer murders. The Zodiac murdered five known victims in Benicia, Vallejo, Napa County, and San Francisco, respectively, between December 1968 and October 1969. He targeted young couples, with two of the men surviving attempted murder. However, by 1988, it was conclusively proven in court that Carpenter was incarcerated during several of the Zodiac murders.

David Carpenter was linked to the following crimes:

Lois Rinna (Lois DeAndrade)

David Carpenter’s first attack was in July 1960 on Lois DeAndrade, now known as Lois Rinna. Lois DeAndrade’s daughter, Lisa Rinna, would become a reality TV star.

He knew Lois from work, and since he had just had a new baby, he asked her whether she wanted to come and see the new family arrival. Lois was also acquainted with Carpenter’s wife, and she felt comfortable going with him.

As agreed, he picked up Lois at a bus stop, but then he started driving down a deserted road. He then attacked her, tried to rape her and then tried to kill her - She was stabbed in the hand and hit in the head with a hammer several times.

Luckily, a military policeman, Wayne Hicks, had seen them drive down the road, and he knew no one was supposed to be down there, so he followed them. Hicks tried to stop the assault, but Carpenter shot at him, and Hicks returned fire, hitting him in the stomach and leg.

Lois said, “I thought that was it. He’s straddling me. He had a hammer in one hand and a knife in another”.

For the assault on DeAndrade, Carpenter was sentenced to 14 years in a federal prison for Carpenter was sentenced to seven years in Prison for kidnapping, rape and attempted murder. However, he only served about seven years. In 1970, he returned to prison after being charged with kidnapping. He was rereleased in 1977 after serving another seven years.

Edda Kane

On August 19, 1979, Edda Kane spent the afternoon hiking the trails of Mount Tamalpais, which overlooks San Francisco’s Golden Gate Bridge. When Edda failed to return home after her hike, her husband called the police and reported her missing.

The police mobilized several officers and K-9 units, and the first search for Edda ended with no clues as to Edda’s whereabouts. The second search began the next day at dawn, and Edda’s naked body was discovered in a kneeling position. Her killer had stood behind her and shot her once in the head execution style. Investigators also found that the killer had rummaged through her purse and stolen her credit cards and a pair of sunglasses. However, she had not been sexually assaulted.

Mary Frances Bennett

On October 21, 1979, Mary Frances Bennett’s “long, agonized screams” could be heard by nearby golfers. Unfortunately, they ignored them.

She was mutilated and stabbed 25 times after she was attacked whilst jogging, then buried in a shallow grave under a layer of dirt and branches. She was found, still warm, by a group of hikers following a blood trail near the Palace of the Legion of Honor at Lands End. One police officer said she had been "butchered." She was only 23 when she was murdered.

Mary grew up in Deer Lodge, Montana., and had recently moved to San Francisco after graduating from an accounting school in Montana. She was an intern at a Post Street accounting firm; when she was killed, she was wearing a T-shirt that read, "Hell's Accountant."

Carpenter was always suspected, but police were never able to bring a case against him for the crime in the 1980s following his arrest. In 2012, Inspector Joe Toomey of the cold-case unit said crime lab technicians had recovered unspecified DNA evidence in December 2011. They learned in January 2012 that it matched a Carpenter DNA sample in a state database. The family always assumed that Carpenter was responsible based on what the police told them at the time.

Barbara Schwartz

Barbara Schwartz, 23, was out hiking with her dog in March 1980 when Carpenter leapt out from behind a tree and attacked her. A female eyewitness who was out jogging that day saw the man attack Barbara from behind with a knife. By the time the eyewitness came back with police officers, she was dead, and the killer was nowhere to be seen.

Thanks to the eyewitness, homicide detectives now had a general description of the killer. The jogger described him as “slim” and somewhere around age 25. Neither of these proved to be accurate. Police also found a pair of bifocal glasses at the crime scene. Days later, a couple of boys also found the murder weapon, a 25-centimeter (10 in) boning knife that proved to have Schwartz’s blood all over it. The glasses turned out to be prison-issued specs, thus suggesting that the killer was a former or escaped inmate.

Anne Alderson

Carpenter attacked his next victim on October 15, 1980. Anne Alderson, 26, had been walking in the woods in Mount Tamalpais State Park. At some point during her hike, she ran into Carpenter, who killed her with three bullets fired from a handgun. Anne’s body was not found until the following year by a passing walker. Like Edda Kane, Alderson had been shot in the back of the head and was found in a kneeling position. However, unlike Edda, Anne had been raped by her killer. When police asked around for eyewitnesses, they received wildly different descriptions of a 50-year-old man seen hanging around the park.

Richard Stowers and Cynthia Moreland

Richard Stowers, 19, California, and Cynthia Moreland,18, planned to get married. However, the couple went missing in mid-October 1980 after setting off for a hiking trip at Point Reyes National Seashore Park. Their bodies were discovered during the search for Diane O’Connell and Shauna May in November 1980.

At the time of their deaths, Stowers was stationed with the US Coast Guard at the Two Rock Coast Guard training base. Moreland recently graduated from Rancho Cotate High School, where she had been a popular cheerleader.

Shell casings found at the scene were a match with those from the Alderson crime scene. As it turned out, the gun used in all three murders was a .38-caliber pistol (some sources say it was a .45-caliber gun) that had been purchased in October 1980. The buyer, Mollie Purnell, bought the firearm at a gun store in San Leandro, California. Purnell then gave the gun to Carpenter, who could not legally purchase firearms because of his criminal record. Purnell would later state that she gave the gun to Carpenter as payment for her debt to Carpenter, who had provided Purnell with several items for her flea market.

Diane O’Connell and Shauna May

On November 28, 1980, Carpenter raped and murdered 22-year-old Diane O’Connell, as well as 25-year-old Shauna May. Both women had decided to hike in the Point Reyes National Seashore Park on the Sky Trail.

Coincidentally, the area was the filming location of John Carpenter’s (no relation to David Carpenter), The Fog, a February 1980 horror movie starring Adrienne Barbeau, Jamie Lee Curtis, Janet Leigh and John Houseman.

Diane was in a group of three hikers and was second in the group coming down the trail. The first group arrived at the bottom, but Diane was nowhere to be seen.

Between 3.10 and 3.20 pm, hikers in the park heard several gunshots.

Rangers, volunteers and police combed the park. One searcher saw a shoe sticking out of some ferns. On closer inspection, he found two bodies, which turned out to be Richard Stowers and Cynthia Moreland. They had been left face down in the underbrush.

Later that day, Diane O’Connell and Shauna May’s bodies were also discovered, found side by side and facedown, making it four bodies in one day.

The killer had stuffed a pair of underpants into O’Connell’s mouth and nose while leaving another pair of bloodstained panties on her arm. A forensic examination proved that Diane had been strangled with a narrow piece of wire or cord whilst still alive. She and Shauna had both been shot in the head. May’s corpse showed ligature marks on her wrists. Her body contained semen in her vagina and anus.

Although no semen was found on O’Connell’s body, she, like May, had been brutally raped before her death. The most troubling part about this double murder was the fact that neither woman knew the other. Therefore, detectives concluded that one woman had come upon Carpenter murdering the other woman by chance, thus sealing her fate.

Ellen Hansen and Steven Haertle

David Carpenter got a new job in February 1981. After his release from prison, he worked for a chain distributor with Econo Quick Print, a small printing shop in Hayward, California.

Carpenter struck in the Henry Cowell Redwoods State Park on March 29, 1981, when he came upon 20-year-old Ellen Hansen and her friend, 20-year-old Steven (or Stephen) Haertle. The pair were having a walk across the Santa Cruz Mountains. They were on Spring break from UC Davis and had just passed the observation tower.

Carpenter told them both that he wanted to rape Ellen, and after sexually assaulting her, Carpenter shot them both. Steve confronted Carpenter and shot Ellen. Hansen died, while Haertle managed to survive despite being shot in the neck. Haertle provided police with a clear description of Hansen’s killer, and he would also later pick out Carpenter in a police lineup.

A 10-year-old girl took a piece of cardboard and drew the shape of a red car. The car turned out to be Carpenter’s red Fiat.

Heather Scaggs

Heather Scaggs, 20, went missing on May 1, 1981. Her decomposing body would later be found in Big Basin State Park. More than any of his other victims, Carpenter had a direct link to Heather. A college undergraduate, she had worked at Econo Quick Print to make some extra money, and David Carpenter was one of her co-workers.

Gossip around the office was that the older Carpenter was a “creep” who wanted to date the much younger Scaggs. Heather did not take notice of this office gossip.

Her boyfriend, Dan Piggle, told Police that Heather had asked Carpenter to give her a ride to Santa Cruz so that she could purchase a car from one of his friends. Carpenter had made it very attractive for her to go and see the car by offering to check the vehicle, loan her money, etc. Fortunately, she had left Carpenter's details with her boyfriend as he was a little concerned.

That would be the last time that anyone saw Heather Scaggs alive. On May 24, 1981, hikers in Big Basin State Park discovered her nude and decomposing corpse. Semen was found in her vagina, and an autopsy proved that she had died from a point-blank shot to the face. Besides the fact that Carpenter was the last person seen with Scaggs before her death, investigators proved that the same .38-caliber handgun had killed both Scaggs and Hansen. This gun was traced back to Carpenter.

Later, it emerged that Carpenter went to dinner and the ballet the evening that he murdered Heather, seemingly oblivious to the murder earlier in the day.

Anna Kelly Menjivar

On June 16, 1981, the body of Anne Menjivar, 17, was found at Castle Rock State Park. Her body was too decomposed to determine a cause of death. Carpenter was never charged, but he was also the chief suspect in the disappearance and death. She disappeared on December 28, 1980. Her family and friends ruled out the idea that the aspiring college student ran away, and this was confirmed when hikers in Castle Rock State Park found Menjivar’s skeletal remains.

Before her death, Carpenter was known to frequent the Continental Savings and Loan, where Menjivar worked as a part-time teller. Eventually, after the awkward and charmless Carpenter was seen chatting with Menjivar, one of the bank’s customers warned management about him. This occurred just days before her disappearance.

Carol Laughlin

Carol Laughlin, 19, worked in the Curry Village gift shop in Yosemite National Park. In September 1979, she mysteriously vanished, and her remains were found at the base of a tunnel near Cookie Cliff some months later. The body was discovered by two men descending Castaneda Wall near Big Oak Flat Road on April 28, 1980.

Carpenter worked for a company supplying items for the gift shop that Carol worked in. Proof that Carpenter was involved in the murder has never been proven.

The Arrest and trial of David Carpenter

David Carpenter was charged with five counts of murder, rape, and attempted rape on July 31, 1981. Due to all the publicity that the murders received in Santa Cruz County, Carpenter’s trial was moved to Los Angeles County. He was convicted on five counts of first-degree murder in the deaths of Richard Stowers, Cynthia Moreland, Shauna May, Diane O'Connell and Anne Alderson. Carpenter also was found guilty of raping two of the women and attempting to rape a third. He was sentenced to death in the gas chamber on November 16, 1984. He remains on San Quentin's death row.

Following his conviction for the Marin County murders, Carpenter was tried and subsequently convicted by a Santa Cruz jury for the murders of two other women, Ellen Hansen and Heather Scaggs.

The same jury also found Carpenter guilty of the attempted murder of Hansen's hiking companion Steven Haertle, the attempted rape of Hansen, and the rape of Scaggs. In 1995, the Santa Cruz convictions were overturned due to juror misconduct. The California Supreme Court later reinstated them.

Carpenter was also the prime suspect beyond the five murders with which he was charged. (Two of those convictions would later be overturned due to juror misconduct.) Although he was never convicted, the evidence against Carpenter in the murders of Edda Kane and Barbara Schwartz is robust.

In December 2009, San Francisco police reexamined evidence from the October 21, 1979, murder of Mary Frances Bennett, who was jogging at Lands End when she was attacked and stabbed to death. A DNA sample from the evidence was matched to Carpenter through state Department of Justice files. In February 2010, police confirmed the match with a recently obtained sample from Carpenter.