Father offers legal help in exchange for ID of son's killer

TEMPE, AZ (CBS) - An Arizona criminal defense attorney is promising a vigorous defense for one of the men involved in his son's death. All he has to do is turn in the actual shooter.

Police believe two men, a driver and a gunman, were involved in the robbery that resulted to the shooting death of Daniel Marco's son.

"What I offer to him is that if he comes forward, I will do my best to ensure that he gets the best defense possible and gets a deal that ensures that he sees the light of day again," Marco said.

Marco went on TV to plea for the driver of the getaway car to come forward and tell the identity of his son's killer.

Zachary Marco, a 21-year-old student at the University of Arizona, was gunned down on his way home from the library during a robbery Sunday.

"I want the kid that killed my son, and I realize there's a tandem there, but one pulled the trigger and I want that guy," Marco said.

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