paul holes, an inspector who had been working on the golden state killer case for decades, initially reached out to rae-venter in march 2017 for her assistance in using genealogy to search for new leads in the case. in october 2017, rae-venter was contributing to the team attempting to identify the killer. rae-venter utilized gedmatch, and provided structure to the team's genetic search efforts. the team isolated a dna sample from a golden state killer crime scene to create a dna profile that could be uploaded to gedmatch, and then worked from profiles that were identified to create family trees. by identifying relatives of the killer, investigators could work back to find a common ancestor and then work forward to identify all members of the younger generations. once all members of a family had been identified, investigators could then start eliminating individuals who were not suspects. in the case of the golden state killer, the team needed to go back to great-great-great grandparents before starting to work forward. multiple family trees needed to be constructed. this information was combined with predictions about ethnicity and physical appearance to narrow down the suspect list. multiple pieces of evidence started to converge when the genetic profiles were considered, including the possibility that the suspect had italian heritage. after the suspect had been identified, new dna samples were collected from the suspect surreptitiously and tested against crime scene samples. the suspect's samples matched those from the killer, confirming his identity. joseph deangelo was arrested on april 24, 2018.