DNA, genealogy lead to arrest in 2012 Arlington cold case murder

[00:00:00]Arlington police announced an arrest in a 14-year-old cold case murder of the woman who you see right here. The detective on this case shared with us pretty emotional and powerful response when we asked her simply about what that moment was like when you can tell a family so many years later that you have finally made an arrest.

[00:00:19]>> That's why being able to share that with a family is why we do this work.

[00:00:41]>> DNA evidence is what linked a North Texas realtor to the murder. Myra Velasquez is now charged with capital murder, but her attorney told us that the DNA evidence does not close this case. Our Robbie Owens now with a closer look at the role of these DNA databases.

[00:01:00]>> And when curiosity strikes about the everyday lives of your family [music] >> access to DNA technology has unleashed a fascination with finding long-lost family.

[00:01:10]>> How is your family woven [music] into 250 years of US history?

[00:01:15]>> And now those databases are becoming game-changing tools for law enforcement searching for cold case killers. It's called investigative genetic genealogy.

[00:01:24]>> It starts with an unknown DNA sample recovered from a scene.

[00:01:28]That sample is then submitted to a publicly accessible genealogy service to identify potential relatives of the unknown DNA profile.

[00:01:37]>> Following a process that police call research-intensive, experts use the DNA sample to build a family tree. And then they essentially shake that tree to see if a potential suspect falls into focus.

[00:01:49]>> At the IGG process I identified a potential suspect 42-year-old Myra Velasquez.

[00:01:58]She was a close friend of the victim who lived just few miles away from the crime scene.

[00:02:03]>> On the morning of January 20th, 2012, Arlington police say it was Velasquez in baggy sweatpants and a hoodie seen in the surveillance video being willingly let into the victim's home, 32-year-old Eresima Chavez. According to court documents, the killer disconnected the DVR which stopped the video surveillance, but left the DVR behind along with the critical drop of blood.

[00:02:28]But does it belong to Velasquez? And does it prove that she's the killer?

[00:02:32]>> Like there is no dispute these two women were friends.

[00:02:36]Your friend's DNA is going to be in your home. Uh my friend's my DNA is going to be in my friend's home.

[00:02:43]>> Defense attorney Frank Sellers has been hired by the family to represent Velasquez.

[00:02:48]>> Look at how he walks up the stairs right here.

[00:02:50]>> He's urging the community to keep an open mind and has been critical of what he's learned so far about the police investigation.

[00:02:58]>> Uh I think that they were so enamored by this new DNA technology that they just uh skipped over the principles of how DNA works. And back in 2012, I can assure you that there were going to be collection issues. This is everybody's worst nightmare.

[00:03:13]Uh but uh there is clearly uh more questions than answers here and we intend to get to the bottom of this.

[00:03:21]>> Robbie Owens, CBS News, Texas.