After almost 50 years, DNA identifies a killer behind two Pennsylvania cold cases: James Richard Clark Sr.

For nearly fifty years, there were no answers for two families in the southwest part of Pennsylvania. This week, the Pennsylvania State Police announced they’ve finally got a name. Investigators say the DNA results have linked the 1970s double homicide of Susan Rush and Brenda Ritter to one man, James Richard Clark, Sr. They think the evidence indicates that there was a serial killer in Washington County at the time.

Police said Clark was a person residing in the area at the time in both cases. Born in 1957, he was 19 years old at the time of Rush’s death and 20 at the time of Ritter’s death. But not in court; he’s not. The case will never go to trial, as he died of natural causes on July 17, 2023, at the age of 66.

After leaving a local shopping mall, 21-year-old Rush from Washington went missing. City police say that she was to meet with her family at church, but she didn’t show up. On the following morning, on Thanksgiving, her brother discovered her car parked along North Avenue. The reports vary slightly in detail, but they are all clear in their results. Investigators determined she had been sexually assaulted and strangled while she was dead inside the vehicle. Detectives pursued a number of early leads, but no one was arrested.

Six months later, another young girl went missing. Ritter, 18, was last seen May 18, 1977, when she left her boyfriend’s house in Chartiers Township. Her remains were discovered on a hillside in South Strabane, about three-fourths of a mile away from her vehicle, while her clothing was spread out some 50 feet away by a state police helicopter. She was also determined to have been sexually assaulted and strangled.

Both cases languished for decades. The evidence found at Ritter’s murder was submitted to a crime lab in late 2008, and a DNA profile of the killer was created. The profile was a step in the right direction, but it did not match any in the databases available at the time. The time off is coming after state police got grant assistance for cold case DNA testing in May of 2022. Additional testing was finished in May 2025, and this testing identified one person for both homicides.

The results were presented this week at a press conference by Cpl. James Petrosky, a criminal investigation assessment supervisor in Troop B. The testing revealed that both women were killed by the same person and “that demonstrates a serial killer was operating in the county during that time,” he said. There is some confusion about whether it was on Wednesday, Thursday, or possibly both, but the announcement remains the same.

The thing that investigators can’t say is the trouble that bothers them. Police have not eliminated Clark from other homicides, Petrosky told reporters. “Believe me, when you are a serial killer, you always are a serial killer,” he said, and thinks that there may be other victims who have not been discovered. The investigation is ongoing, and the state police are seeking anyone with information about the incident to come forward.

The families of both women have been notified, and they have asked for privacy. An answer after all these years is not the same as peace, and the people who have been cherishing Rush and Ritter have now seen their grief reopened. That alone is enough to take this news with a grain of salt.

Another example of forensic science continually pushing the boundaries of what’s possible is the case in question. In the 1970s, the crime scene was collected without any name. That material required improved laboratory techniques, hard work and perseverance by cold-case investigators and funding to make an identification. Similar advancements have been reported in various departments within the United States in recent years, and many of the crimes that have been solved were apparently unsolvable. Other unsolved cases could turn to this one for some hope now.

But such a result can only be so useful. A name is a closing that ends one question but does not have the power to reopen or provide a judgment. In this case, Clark will never be held responsible for what the police did, and if there were other victims, it might be up to the same careful science to locate them. Washington County now has a name for the man they believe was responsible for two of their most heart-wrenching unsolved murders, and a warning that the mystery might not be over yet.

Resources

1. https://abcnews.com/US/dna-testing-confirms-serial-killer-pennsylvania-1970s-state/story?id=137882432
2. https://local21news.com/news/nation-world/dna-links-serial-killer-to-pennsylvania-cold-case-murders-dating-back-to-1970s-police-murder-murderer-killed-homicide-death-investigation-sexual-assault-strangulation-strangled-true-crime
3. https://abc7news.com/story/dna-testing-confirms-serial-killer-washington-county-pennsylvania-1970s-state-police/20019693/
4. https://wgxa.tv/news/nation-world/dna-links-serial-killer-to-pennsylvania-cold-case-murders-dating-back-to-1970s-police-murder-murderer-killed-homicide-death-investigation-sexual-assault-strangulation-strangled-true-crime