CALIFORNIA COMMERCIAL TRUCKING ACCIDENT: How can a commercial trucking company be held responsible for a California auto accident?

This answer depends.

It depends on whether an employment relationship is established between the truck driver and the commercial trucking company. Was the commercial truck driver within the course and scope of his or her employment with commercial trucking company?  If this relationship is shown, the commercial trucking company can be held legally liable (at fault)  for the truck driver's (employee) negligence under a California legal theory known as "respondeat superior."

However, establishing the liability of a commercial trucking company can become problematic when a truck driver is an independent contractor of the company. In such a situation, the primary issue becomes the amount of supervision and control exercised by the company.  Sometimes an employer and employee relationship can be shown if the commercial trucking company performed great control over the truck driver making him or her an employee and not an independent contractor.