A 17-year-old is pleading not guilty to shooting dead a four-month-old boy as he was being fed in a parked car.
Alfonzo Landa, of Los Angeles, is charged as an adult over the September 27 death of Andrew Garcia.
He is also charged with attempting to kill six other people and carjacking.
The shooting came after a family party celebrating a baptism at a San Fernando Valley banquet hall.
Police say the baby died from a bullet to the head after Landa argued with a gang member standing outside the car and opened fire.
The gang member and a pregnant woman feeding the baby inside the car were injured. Four others near the car were not hit.
A second suspect remains at large.