Tiffany Frederick, 21, of Quail Road in Barnwell, was killed Dec. 15 in a single-car crash in Allendale County, said Allendale County Cornorer Marion Riley Jr.
Lance Cpl. Sonny Collins of the S.C. Highway Patrol said Frederick was a back seat passenger in a 2004 Crown Victoria that was traveling east on Carter Road, just outside Kline around 2:30 a.m.
He said the driver, whose identity has not been released, ran off the left side of the road and struck a tree.
There were four people in the car and none were wearing seat belts at the time of the crash, Collins said.
"No names are being released at this time until the investigation is completed," he said.
Concluding the investigation, Collins said charges may be filed.