DNA confirms one killer linked to two 1970s deaths in Pennsylvania

State police in Pennsylvania have closed two cold cases dating back to the 1970s. DNA evidence has linked the deaths of Susan Rush and Brenda Ritter to a single suspect. The announcement came during a press conference on Wednesday in Washington County.

Authorities identified the suspect as James Richard Clark Sr. He was born in 1957 and died at age 66 in 2023. He lived in the Washington County area during the relevant time frame. He was 19 years old when Rush was killed and 20 years old when Ritter was killed.

Cpl. James Petrosky, the criminal investigation assessment supervisor with Troop B of the Pennsylvania State Police, presented the findings. He stated that testing confirmed a serial killer operated in Washington County during that period. Additional DNA testing conducted in May of 2025 identified the same offender for both homicides.

Rush was found dead in 1976. Her body was in the trunk of her car. Authorities determined she had been sexually assaulted and strangled. Ritter, who was 18, was killed in 1977. Her remains were discovered on a hillside. She also suffered from sexual assault and strangulation.

The families of both victims have been notified. They have requested privacy. Petrosky told reporters that investigators are not ruling out other potential victims. He said he believed there could potentially be more victims out there. The investigation remains ongoing.

Petrosky noted that Clark was a serial killer. He added that once a person is a serial killer, they are always a serial killer. This assessment guides the current search for other cases.