Justice took more than 40 years to arrive. But thanks to the persistence of some members of the Ventura County law enforcement community, the cases have finally been closed on some violent crimes.
Prosecutors say efforts to solve two cold case home invasion sexual assault cases in Ventura led to the discovery of a serial rapist, whose crimes spanned decades and multiple states.
Unraveling the mystery started with the work of a special investigative team. The county established the unit with the Ventura County District Attorney’s Office and the Sheriff’s Office to use new technology to try to solve 2,800 unsolved sexual assault cases dating back to the 1970s.
"The Ventura County Sexual Assault Kit Initiative is funded jointly by the U.S. Department of Justice and Ventura County," said Brent Nibecker, Ventura County’s Acting Chief Deputy District Attorney. "The goal is to test all sexual assault kits in existence in the county using modern DNA technologies."
He said they focused on two home invasion sexual assaults in Ventura homes in 1982 and 1983. Both cases went unsolved at the time.
But they did new tests using the latest technology.
"These kits were sent out for testing in 2023. The results were received by our crime lab, and then our lab does an independent review," said Nibecker.
After the results were confirmed, the DNA was loaded into a national database to see if it would get any hits.
The DNA not only linked the two 1980s Ventura County crimes, but it also turned up connections with three other attacks in other states in the 1990s.
"The two (Ventura County) profiles matched to each other. We knew it was the same suspect who had committed the 1982 and 1983 sexual assaults," said Nibecker. "Shortly thereafter, it matched across state lines, with two cases in Michigan, and one in Ohio."
The investigators thought they had identified the serial rapist. It was a one-time Ventura County resident named Sean Patrick McNulty.
"McNulty was born in the Bay Area. He moved to Ventura when he was young. He graduated from (Ventura's) Buena High School. He joined the military, traveling throughout the 1980s. Beyond that, we don't know a whole lot about what he did. It's a bit of a mystery."
They discovered the man they sought was dead. They found a gravestone in a Ventura cemetery. It turned out he wasn’t buried there, and he had been cremated. They thought there was no way to get the DNA evidence they needed to make a solid link.
"One of our partners, Audrey Hine, with the FBI's Violent Criminal Apprehension Program, helped us. We had given her McNulty's name. She ran it through their system and found there had been a case against him in Bloomington, Indiana," said Nibecker. "In that case, he was a suspect in a sexual assault case.
Nibecker said they found out that, as Bloomington Police detectives had closed in on McNulty in 1997, the then 38-year-old man had taken his life.
Fortunately, the Indiana police department had kept evidence from their rape case. There was DNA evidence, enough to make a definite connection between McNulty and the string of crimes.
The prosecutor said they were able to find some of the survivors of the attacks, to let them know their cases had been solved, and the predator was dead.
"Investigator Yumi Kirk was able to make contact with one of our survivors," said the Deputy DA. "She was overjoyed to know that law enforcement hadn't given up. She told Kirk she had waited 40 years to get answers about who had done this to her, and she was beyond grateful."
But, Nibecker said the investigation into McNulty isn’t over. They believe he may have been responsible for a number of other attacks still classified as unsolved.
The prosecutor said an incredible amount of patience and teamwork went into finally solving the mystery. He feels it’s humbling to finally bring closure to some of the attacks' survivors.
