Did Robert Durst kill Karen Mitchell or was she a victim of a serial killer? Part of the Humboldt Five, Karen belongs to an infamous group of women who went missing from the Emerald Triangle.

“Every day I think about where she would be, if she would have a family, what would her job be, how our conversations would go, how much fun we would be having, the trips we would take,” Mary Casper said.

Karen is remembered as a kind young woman who had tenacious advocacy for the environment. Friends described her as fun and always making people laugh. Not long after she was born, Karen’s parents divorced and she grew up in Whittier, California with her mother and her brother. She moved to Eureka at age 13, just three years before she disappeared. Karen, along with her mom Mary Casper, made the decision that living with her aunt and uncle, Bill and Annie Casper, would be better for the young woman. Mary was single at the time and she spent a lot of time working and was concerned that Karen was not being supervised enough. Both agreed that it would be safer for her to live in Eureka. Though she lived with Bill and Annie, Karen would go home to Orange County on vacations and summer breaks.

Karen was a very motivated teenager. At the age of 16, she was determined to graduate high school a year early so she could begin studying environmental sciences at college. In fact, she was in the midst of applying to various colleges at the time of her disappearance.

“She was her own person, very vivacious, very strong, very smart. She was an A student,” Annie Casper recalled. “She was opinionated, but she had an agenda and she wanted to help change the world.”

The day she went missing

It was a busy time for Karen as she was applying to various colleges. She spent the morning on the phone with her mother working on them.

“We were talking about plans for the summer. We were going to take some college courses together,” Mary Casper said. “We were actually filling out paperwork to start applying for college, we were filling out FAFSA forms. That was happening all that morning. We were busy girls.”

Because it was Thanksgiving break, Karen was helping out at her aunt’s shoe store, Annie’s Shoes, at the Bayshore Mall. Later that afternoon, Annie left to go to her job at a daycare center at 2:45. Her aunt offered her a ride, but Karen declined, saying that it was a sunny day. The daycare was only about a mile away.

Later that evening, Annie went to the Coastal Family Development Center to pick Annie up; however, the lights were out and the staff told Annie that Karen did not make it in that day.

A former police officer told investigators that he had to slam on his brakes to avoid hitting a car which he then witnessed a girl who resembled Karen getting into. The vehicle was a light blue 1977 Ford Granada. It had California license plates and the word "Eureka" was imprinted on the rear license plate frame. The man is described as 60-70 years old with balding light gray or sandy blonde hair and grey or green eyes. He had a small build, a large nose that had likely been broken in the past, and he wore "prescription-type" eyeglasses and a long-sleeved blue button-up shirt. Neither the man nor the car has ever been identified despite composite sketches being created of both.

The investigation

Eureka police department immediately began investigating the crime. A command center was set up in a local hotel for family and volunteers. Police crisscrossed the west coast tracking down 1,200 vehicles matching the description provided by a witness.

In 1999, investigators interviewed Wayne Adam Ford after he walked into a sheriff’s office and confessed to killing a woman. Ultimately, they could not link Ford to Karen’s case.

In 2004, the largest land search since Karen disappeared was conducted. They traversed the area with cadaver-sniffing dogs and conducted many new interviews. Again, they failed to turn up any leads.

Many have also tried to link Robert Durst to Karen’s abduction. Durst has an uncanny resemblance to the suspect sketch and was known to visit Annie’s shoe store following Karen’s disappearance. Investigators have not been able to rule him out. Durst passed away in prison in January of 2022.

Where the case stands today

Karen’s case is still open. If you know anything about the disappearance of Karen Mitchell, please contact the Eureka Police Department at (707) 441-4060.

Check out the other Humboldt Five Cases: Christine Walters, Jennifer Wilmer, Danielle Bertolini and Sheila Franks.