Sheriff's Office links 1987 Sposito murder, other assaults to man who killed himself in 1994

Cold case solved through hard work, DNA testing

On June 13, 1987, Cathy Sposito was sexually assaulted and brutally murdered while hiking the Thumb Butte Trail in Prescott. Now 36 years later, the Yavapai County Sheriff’s Office (YCSO) is shedding light in this decades-long murder mystery.

While not “conclusive,” the YCSO can “definitively” say that Bryan Scott Bennett is responsible for the death of Sposito, Sheriff David Rhodes said during a press conference on Friday, Aug. 25. Bennett was 16 at the time and a junior at Prescott High School.

“The Sposito murder was an aggressive overkill,” Rhodes said.

Sposito, 23, from Brooklyn, New York, was a student at Prescott College at the time of her murder. According to the YCSO, she rode her bicycle to the trailhead at approximately 7 a.m. and began hiking. Later that same day, her lifeless body was found on the trail.

Her death was due to blunt force trauma to the right side of her head, the result of two rocks and a ratchet wrench. She also was shot in the face through her eye by a .22 caliber weapon, but it didn’t penetrate the brain, Rhodes said. She also was stabbed on the side of her head.

Sposito was discovered down a ways from where the blood trail began, leading to her body, police reports stated. Other hikers in the area heard her screams and rushed to help but were too far away. By the time they arrived, they found nobody around.

Botched medical exam

The medical examiner in Phoenix who handled Sposito’s case ran the DNA test; however, in the process got his DNA mixed into the testing, according to the YCSO. Therefore he accidentally came up as a “suspect.” And with technology being what it was at the time, the DNA testing was deemed unusable and therefore the case went cold, YCSO officials said.

And the attacks continued

In April 1990, a similar attack of a “Jane Doe” female in her 30s also occurred on Thumb Butte Trail where a male perpetrator held a rock over her head while threatening to kill her. And once again there were no suspects – the DNA couldn’t be linked to anyone – and that case went cold as well. The woman survived; her name is being withheld for privacy reasons.

Years later in 2017, YCSO took on cold case volunteers who worked diligently on the Sposito case and reported finding many similarities to the “Jane Doe” assault that took place in 1990, the YCSO stated.

And these volunteers applied for a state grant that would pay for a private lab called Parabon that conducted “familial DNA” genealogy analysis on the DNA belonging to the “Jane Doe” victim. This type of test utilizes a family members’ DNA to provide leads for identification of an unknown person.

And a few years later in 2020, it was determined that the DNA tested was connected to one of two Bennett brothers who resided in Yavapai County when both the Sposito murder and the “Jane Doe” attack took place.

Volunteers then continued putting the pieces together and were able to determine that Bryan Scott Bennett was tried but acquitted of an attempted sexual assault at a drinking party in Chino Valley in July 1990, three months after the “Jane Doe” attack.

It was also discovered that an arrest was made for another sexual assault and kidnapping of a Prescott woman, Renee Sandoval, near the post office in 1993, which went unsolved, but is believed to be connected to Bennett as well.

During Friday’s press conference, Sandoval emotionally spoke about her attack, and forewarned the public to always be vigilant of their surroundings.

“All the young people out there, watch yourself, even older people too. Be cautious of your surroundings. I tell my grandkids that all the time and my mom,” Sandoval said.

According to YCSO, Bennett committed suicide by way of a self-inflicted gunshot wound to the head by a .22 caliber in Kentucky in January 1994. No suicide note was found. Nonetheless, YCSO were determined to piece the puzzle together in hopes of bringing closure for all persons involved.

The familial forensic analysis continued and in November 2022, Bennett’s body was exhumed per a court order, and DNA was retrieved via cheek swabs taken from Bennett’s brother and a daughter, who was born in February 1989.

“When you have multiple contributors, the only thing you can do analytically is develop a likelihood, which is what we ended up doing being collected over time and everyone who is a person of interest was plotted out on a chart along with the DNA that was discovered on the ratchet wrench and we were able to decipher DNA presence. And obviously number one contributor was the victim, Cathy Sposito, and number two contributor by far was Bryan Bennett,” said Richard Finston, cold case investigator volunteer with the YCSO.

In March 2023, Parabon Labs determined that Bennett was “definitively” the person responsible for sexually assaulting “Jane Doe” in 1990. And taking into consideration the parallels of that case and the Sposito murder, the YCSO had the DNA from the Sposito case analyzed despite the contamination issues from 1987.

Despite the Sposito murder occurring so many years ago, it’s still on the forefront of many minds.

“Advancements in DNA, both direct and familial, allows for closure for everyone involved in cold cases such as Cathy Sposito. With such information available nowadays, there’s a good chance you get a knock on the door that justice has been served,” said Prescott Mayor Phil Goode, who attended the press conference.

And judging by Bennett’s history, the YCSO believes there are more victims for whom they would like to bring closure to, who may not have felt comfortable to speak out at the time of their assaults. Anyone with additional information, is urged to contact the YCSO Silent Witness at 800-923-3232.

Editor’s Note – Rhodes clarified there is no relation between the Bennett brothers in this case and District 1 Arizona Sen. Ken Bennett or his family.

Reach Debra Winters by email at dwinters@prescottaz.com, or call 928-445-3333, ext. 1111.