Transcript for 'Familial DNA' leads to cold-case arrest
We'll start with an arrest in a cold case in Houston thanks to a cigarette butt and some cutting-edge science. A murder suspect is now in custody after police tracked him down through a controversial technique and Marci Gonzalez joins us with more. Hi, Marci. Reporter: Good morning. This case was wide open for more than a year until police in Texas say something called familial DNA testing finally helped lead them to that suspect. Investigators say it was a brutal murder. 50-year-old Natalia shal found dead inside her Baytown, Texas, apartment on mother a day 2016 stabbed in the back 30 times. Investigators had evidence from that gruesome crime scene, a sketch of a possible suspect and DNA. But for more than a year no arrest. But then that DNA was tested for something called a familial match. DNA markers genetically similar to someone already in jail for another crime and investigators say there was a hit on an inmate convicted of sexual assault and that inpate's brother would become the prime suspect in shal's person. They identified a person of interest in the case as 29-year-old Byron Collins of Baytown. You are charged with a felony offense, capital murder. Reporter: Police discovered he lived in the same apartment complex as shal but that alone was not enough. Investigators in Houston needed a stronger link. So they started surveillance on Collins and say they saw him throw out a cigarette. DNA from that cigarette police say linked him directly to the crime scene. We get these cases, we don't stop. We work them until we can't work them anymore. Reporter: Familial DNA is controversial and criticized by some as invasive. The fact that there is in technology doesn't mean that we should give up on our privacy. Reporter: But the technique first used in Europe back in 2003 has been pivotal in several high-profile cases in the U.S. Including the grim sleeper case in California. Familial DNA helped arrest Lonnie Franklin sentenced in the death of women over two decades. Only a handful of states allow familial DNA testing and while the method has proven success fulg in multiple cases civil liberties groups says it has also led to false leads. Dan and Paula. Tricky issue. Marci, thank you very much. We appreciate it.
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