Christopher Licon has pleaded not guilty to murder charges in the killings of 27-year-old Angel Jaquez and Jaquez's son, Xavier Daniel Jaquez.
Sanitation workers found the boy's body in an alley in Phoenix in December 2010, one day after the boy's father was found dead at their south Phoenix home.
Police suspect that Licon grabbed a gun and shot Jaquez in the back of the head as Jaquez sat watching television, according to the court document.
Authorities say Xavier was in the home at the time and either saw or heard the killing.
Investigators believe the boy was killed because of what he knew.
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