Three days after the 19-year-old black woman was killed in Riverside, 40 miles east of Los Angeles, the case is rousing political and racial passions, with relatives accusing the police of murder and the officers involved failing to produce a satisfactory explanation.
It appears Ms Miller pulled into the petrol station in the early hours of Monday because of a flat tyre. When her cousin, Anthonete Joiner, arrived to help, she found Ms Miller lying in the car with her seat pushed back, the radio blaring and the heating on full blast. According to some reports, she was also foaming at the mouth.
The police arrived in response to an emergency call from Ms Joiner and began pounding on the windows of the car to elicit a response. What happened next is, as yet, unclear, but the result was that Ms Miller and her car were riddled with as many as two dozen rounds of ammunition.
At first the four officers, three whites and one Hispanic, claimed Ms Miller had fired a round from her pistol, but a police spokesman later said that was not certain. Two of the officers have been suspended pending an investigation.
Ms Miller's relatives claim she did not even reach for the gun. "They murdered my niece," said Lenora Butler, an aunt. Local civil rights groups have appealed for calm until the facts become clearer.
Racial tensions were already mounting in Riverside because of a debate about the merits of naming a local high school after Martin Luther King.