Often more than one party: the truck driver, the trucking company, the cargo loading company, or the maintenance provider. Federal regulations and the truck's black box data usually determine who is responsible.

Commercial trucks record speed, braking, and hours of operation electronically. That data can prove what happened in the seconds before a crash — but it can be overwritten, so it must be preserved quickly with a preservation letter.

Usually yes. When the driver was working at the time of the crash, the trucking company is generally responsible for the driver's negligence, and company practices like maintenance and scheduling may also be at issue.