Texas cold case cracked after 43 years

(KRIS) - More than 40 years after an Alice, Texas police officer was murdered on duty, investigators think they know who pulled the trigger.

Officer Matt Murphy was shot to death while making a traffic stop in December of 1974. Now 43-years later, authorities have issued an arrest warrant for 70-year-old Roberto Lopez, the man they believe is responsible.

Lopez is already in prison, serving a life sentence in Alabama for armed robbery. Now he faces a capital murder charge. The Texas Rangers and the Alice Police Department reopened the investigation into the murder this January, after a prison warden in Alabama said a "jailhouse snitch" had information that implicated Lopez in the shooting.

It has been four decades since his death, but the pain of loss is still fresh for those who worked with Murphy.

"I was totally angry," Doroteo Martinez, a former Alice police officer, said. "I wanted to ask questions: who, when, where, and why?"