DNA evidence led to arrest in nearly 20-year-old San Marcos cold case

A nearly 20-year-old cold case may be solved after DNA evidence led to an arrest last month. 

Police arrested 41-year-old Ricardo Rodriguez in Florida in connection to a violent sexual assault in San Marcos in 2004.

On October 9, 2004, San Marcos police responded to the home of a woman who said she had been assaulted in her bedroom. The victim said she never saw the man’s face, but a DNA sample from the suspect was collected at the hospital. It was sent for testing but didn’t come back with many leads.

"The technology that we use didn't exist, you know, many years ago," Bureau of Justice Assistants Department of Justice Forensics Unit Supervisor Dr. Angela Williamson said.

This kit sat on the shelf for years. "We’re thankful these kits were kept," Dr. Williamson said.


Years later, when law enforcement followed up with the victim, she still wanted justice.

"It doesn't matter how old the kit is, how old the case is, this is a person waiting for answers and often that answer is in that kit," Dr. Williamson said.

In March, Texas DPS found a possible lead connected to Rodriguez, who grew up in San Marcos but was now living in Tampa. The Texas Rangers and the Hillsborough County Sheriff’s Office in Florida worked together to get a DNA sample from Rodriguez. It was compared to the one in 2004 and it matched.

"In terms of DNA providing that key lead, that's what we're seeing now," Dr. Williamson said.

It’s also providing answers to victims through the National Sexual Assault Kit Initiative which gives funding to law enforcement agencies to test kits, investigate, and provide resources for survivors. At least 200,000 cases are getting looked at again.


"It is acknowledging what happened to the victims and giving them a chance at justice. They won't always get it, we have to acknowledge that, but letting them know that everything that can be done is being done with their cases, it doesn't matter when it happened," Dr. Williamson said.

Dr. Williamson said the results from these tests are connecting offenders with other crimes.

"What we're seeing on SAKI is that the majority offenders are serial in nature, meaning they don't stop, they keep going, but they're crossover offenders and what that means is they're doing homicides, kidnappings, robberies, rapes, rape homicides, rapes by themselves, homicides by themselves," Dr. Williamson said.

She said one kit often leads to 20 other different types of cases.

"If you don't stop these offenders, they're not going to retire on their own," Dr. Williamson said.

Rodriguez is facing two counts of aggravated sexual assault.