Background
Oscar Grant had been celebrating New Year's Eve with his friends on the Embarcadero in San Francisco, and was returning to the East Bay in the lead car of a BART train bound for Fruitvale.[3][14] BART offered extended service and a special "Flash Pass" for the New Year's Eve holiday.[7][15] At approximately 2:00 a.m. PST, BART Police responded to reports that up to 12 people were involved in a fight on an incoming train from the West Oakland BART Station and the participants were "hammered and stoned."[3][4][16]
Officers removed Grant and several other men suspected of fighting from the train and detained them on the platform. Grant and another man ran back onto the train after being detained, but Grant voluntarily returned to the platform when officer Tony Pirone grabbed the other man and dragged him from the train.[3] Pirone handcuffed Grant's friend, angering other riders.[3] Pirone then lined up Grant and two other men against the wall.[3][17] According to Mehserle's motion for bail, Pirone confirmed with the train operator that the men detained were involved in the fight.[5] When five other officers, including Johannes Mehserle, arrived at the Fruitvale station, they found the situation chaotic.[3][18] Mehserle's partner on duty, Officer Jon Woffinden, said the "incident was one of the most frightening he had experienced in his 12 years as a police officer."
BART police had been on edge before the shooting because two guns had been recovered in separate incidents along the rail line over the previous hour.[27] Immediately before he arrived at Fruitvale, Mehserle was involved in an incident at the West Oakland station where a teenage boy with a semi-automatic pistol