In a news release Monday afternoon, police said Matsuda hit the man in the face during the argument. Matsuda also hit the woman when she intervened, police said.
The male partygoer, whose name was withheld, ran inside the house for backup, police said. That's when other partygoers, including Clifford, reportedly went after Matsuda.
The fight escalated, with Matsuda reportedly getting a baseball bat from his garage and the partygoers then getting two bats from their house.
Matsuda chased the partygoers back across the street, striking a woman on the arm with his bat in the process, police said.
An unidentified man then hit Matsuda in the head with a bat, and Clifford allegedly started hitting Matsuda with a bat as Matsuda lay on the ground. Other partygoers are accused of hitting and kicking him as he lay on the ground.
The autopsy also revealed Matsuda was stabbed.