In November of 1975, 20-year-old Sherly Ann Norris left her job as a secretary at the Crime Prevention Institute of Texas in San Marcos to go home for lunch. She was later found dead in her bathtub, and the identity of the man who raped, strangled and drowned her remained a mystery for almost four decades.

After DNA samples from the scene of the murder were submitted to a national database in 2010, investigators got a hit with 59-year-old Willie Jenkins – a man convicted of four rapes in Texas and California.

Jenkins, a former Marine who was in Texas on leave at the time of Norris’ murder, is on trial for the brutal crime. He faces the death penalty. Opening statements began Tuesday in Hays County, where a jury was shown evidence and graphic photos of the crime scene.

Investigators say the evidence suggests that Norris, who was described as a cautious person who always locked her doors, fought back against her attacker. She had taken a self defense class in the weeks before her murder, and she apparently kicked a hole in the wall of her bathroom as she struggled with her attacker. She was discovered with two scarves tied around her neck while submerged in a tub full of water.

Today, Judge Gary L. Steel will consider a defense motion to suppress DNA evidence in the case – Hays County’s first death penalty case in almost 20 years.