Sgt. Gene Sapino says Balam was shot once in the side at the park at 1101 NW Second Street. That killing appeared to be a result of a dispute over a woman, possibly Walker's girlfriend.
Balam's family argues the girlfriend should also be charged since she allegedly drove Walker to the scene.
"That's her car, she drove him there, he killed my cousin and they let her go free. I'm upset about that," says Decarla Balam, the victim's cousin.
Police say Walker has an extensive criminal history including arrests for drugs and other non-violent crimes. He appeared in court today on both charges.
Police have not yet recovered the firearm used in the shooting.
The family is preparing for Balam's funeral, which is scheduled for Saturday.