For 17 years, Cmdr. Penny Dunn of the San Marcos Police Department worked to find out who killed Sheryl Ann Norris in San Marcos in 1975.
Dunn, who has been a police officer for 27 years, was a sergeant with the San Marcos police when the case came to her attention in 1996, she said Tuesday during the capital murder trial of Willie Jenkins, who has pleaded not guilty in Norris’s killing.
The first time Norris’s sister called her for an update, Dunn didn’t know what case the woman was talking about.
Norris was found dead in her San Marcos apartment Nov. 24, 1975, raped, strangled and drowned in her bathtub, a case that had been cold for 10 years before Dunn joined the department.
Dunn started digging.
She located the old files in the case, talked to the few remaining investigators who had worked on the case or had visited the scene. Technology had come a long way since the early days of the investigation, Dunn said, so she prepared to submit physical evidence to the Texas Department of Public Safety’s crime labs. Finding the killer became a persistent concern for Dunn, who quietly advanced the case without a break for nearly two decades.
DNA analysis conducted in 1997 of semen found in the victim’s body was used to rule out many of the early suspects. But the technology hadn’t come far enough to extract enough information to submit a DNA profile to a national database.
Dunn watched out for murder cases in other cities and states and requested suspect DNA profiles to compare one-to-one with the sample in the Norris case.
“The thing I would look at is what type of crime it was and look at how old the person was to see if they could have committed a crime in 1975 in San Marcos and had they ever been in Texas or Central Texas,” she told the jury.
“I had my doubts,” she admitted. “Every single time I did a one-to-one comparison … and there was no match, it was a really horrible feeling.”
In 2010, MiniFiler DNA analysis technology, which works well with old samples, was introduced to the DPS crime lab and the Norris case was one of the first in line.
Technicians were able to extract enough information to submit the profile to the national database, Dunn said, and a month later it came back with a match.
“I think you could have peeled me off the ceiling,” Dunn said. “Everything changed at that point.”
The database identified Willie Roy Jenkins, now 59, a convicted rapist being held in a mental facility in California, as a match.
When Dunn interviewed Jenkins, she said he offered no explanation about how his DNA could have ended up at a crime scene in San Marcos. Investigators later discovered that Jenkins, who served in the U.S. Marine Corps at the time of the crime, was on emergency leave from Nov. 23-Dec. 5, 1975 and had permission to travel home to Texas. Prosecutors have said that he was in Texas to visit his wife, who was hospitalized in San Antonio.
Further DNA matches for Jenkins were found in 2011 on a blouse Norris was wearing when she died, prosecutors say.
Defense attorneys have motioned to suppress DNA evidence in the case, and Judge Gary L. Steel said that he will consider that motion Thursday.