The simple answer is always yes! You should always call the local law enforcement or the California Highway Patrol if you were involved in a accident on the freeway or highway. Whether you were in a car accident, truck accident, or motorcycle accident that has caused personal injuries or it has not you should always call the police to document the scene and provide a concise snapshot of the accident scene and in some cases the police officer will conclude liability or who was at fault.
I have had clients that have call local law enforcement after a accident only to be told that an officer would not respond to the scene if there were no injuries. The dispatchers almost always request that the parties exchange insurance information and safely exit the accident area. In these cases, it is vitally important that you document everything considering the police will not. If you have a smart phone you should take pictures of the vehicles, the roadway, license plates, drivers licenses, and insurance cards. You may even ask that you can take pictures of the individuals in the car to avoid a future bodily injury claim if there was nobody injured in the accident.