PRESS RELEASE
PITTSBURGH — Cybergenetics Corp assisted the Washington County, Pennsylvania, police in their DNA identification of serial killer James Richard Clark Sr, who raped and murdered two young women fifty years ago.
Susan Rush was raped and strangled in November 1976; her body was concealed in the trunk of her car. Six months later, Brenda Ritter’s nude body was discovered in a field two miles away; she too had been raped and strangled.
In May 2025, the Pennsylvania State Police (PSP) sent Cybergenetics DNA data. The company offers a free TrueAllele® data screening service for DNA evidence. The PSP asked us if the two cases shared DNA from an unknown person.
The Susan Rush swab included a sperm fraction from green pants. The Brenda Ritter swab showed spermatozoa from pubic hair. Different DNA labs had developed conventional autosomal DNA data from these evidence items using different STR kits.
From the case data, TrueAllele software isolated the unknown male genotypes. TrueAllele then compared the two evidence genotypes, finding a match strength of a million. This new cold-case DNA lead linked the two cases to the same unknown man — the serial killer.
Cybergenetics testing established that the same offender murdered both Susan Rush and Brenda Ritter. TrueAllele analysis confirmed there was a serial killer in Washington County during the 1976 to 1977 timeframe. We notified the PSP.
Later work by public and private DNA investigators identified this unknown man as James Richard Clark Sr, now deceased. This week the police announced that Clark committed the sexual assaults and homicides of both Susan Rush and Brenda Ritter.
Pittsburgh-based Cybergenetics was founded in 1994. The company pioneered the accurate, automated, and objective analysis of complex DNA evidence. In 2005 the company’s TrueAllele® technology helped identify victim remains in the World Trade Center disaster.
Crime labs use TrueAllele to solve their hardest DNA cases. Cybergenetics has assisted over 600 agencies on over 1,600 cases involving challenging DNA. TrueAllele has been extensively tested and is accepted by courts as reliable evidence. It has helped exonerate 18 innocent men.