After years of dead ends and false convictions, the homicides eventually led to Joe Biden signing a federal law in 2022 to allow victims’ families to ask for cold cases to be reopened.But the murders still remained unsolved for nearly 34 years – until now.Law enforcement officials announced on Monday a “significant breakthrough” driven by new technology around ballistics and DNA, said Austin’s mayor, Kirk Watson, at a press conference on Monday.A photo of Jennifer and Sarah Harbison, displayed as police announce a break in the case. Photograph: Bob Daemmrich/Zuma Press Wire/ShutterstockThe evidence points to Robert Eugene Brashers, who was identified after his death as a serial killer. More murders may be added to his toll as DNA analyses become more advanced and widespread.Scientific and technological advances are identifying previously unknown serial killers like Brashers.“The only physical evidence located at that scene has been matched to him,” said Austin’s chief of police, Lisa Davis.The case isn’t closed yet, but this is a “major step”, and Brashers is believed to be the sole perpetrator, Davis said.Eliza’s sister Sonora Thomas, now a therapist, said her mind was split in two when Eliza was killed.“One part of my brain has been screaming, ‘What happened to my sister?’, and the other part kept repeating, ‘I will never know.