He preyed upon older women, some in their 70s, one as old as 99, police said. He raped them. And sometimes, authorities said, he beat them to death.

During the mid-1980s, police had a suspect for these acts, Henry Lee Bethune, but no hard evidence linking him to a crime scene. Then a sergeant in the Houston Police Department‘s homicide division, Jim Yarbrough, read a magazine article on the first use of DNA to solve a crime mystery in England.

Yarbrough called the pioneering scientist, an English geneticist named Alec Jeffreys, setting off a chain of events that would lead to the conviction of Bethune — one of the first Texas criminals convicted with DNA evidence — on charges of raping a 74-year-old woman.