Investigators are analyzing wreckage and eye witness accounts to determine who was at fault in an accident between a semi truck and a UCSF shuttle bus in San Francisco. At least one witness said the accident was caused by the shuttle running a red light. The accident killed one person, a doctor who worked at San Francisco General, and injured 4 others.

According to police reports of the 2011 crash:

The crash happened at Octavia and Oak streets at 6:20 a.m. when a 2007 Peterbilt tractor-trailer truck carrying four cars collided with the Ford shuttle bus taking UCSF employees to San Francisco General Hospital.

Even if the bus did run a red light, the semi truck driver may have been partially at fault if he was speeding or distracted. Liability in these cases can be complex.