The attack happened during a barbecue outside a home in Atwater Sunday evening.
Investigators say 61-year-old Joseph McDonald - a transient - and others were guests at the home. But after some heavy drinking, the gathering turned ugly during a scuffle between 30-year-old Antonio Cruz Guzman and McDonald.
Investigators also say Guzman attacked McDonald with a machete, leaving him with severe cuts to his neck and arms.
"A witness told officers that they saw the suspect who fled the scene use what we call a machete," said Lt. Sammy Joseph. "And took the office where the suspect had dumped the machete as he fled the scene."
The suspect was found hours later at a trailer home not far from the crime scene.
McDonald died from his wounds at a local hospital. Guzman now faces murder charges.