Per the CHP, there is no concept of a "fast lane" or a "passing lane" on a freeway. While it is customary and polite for slower cars to drive on the right, they're not required to do so.
It varies from state to state. Some states prohibit passing on the right. Some don't. In Ohio in the late 90's, the law was that anything which you could drive on was a lane. I was slowing down in the right lane and signalling a right turn into a parking lot, right when the young lady behind me decided to drive over the empty parking spaces on the right-hand side and pass me. There was a fender-bender. The policeman summarily ruled it was my fault, because according to the law in Ohio, I was responsible for looking out for someone passing me in the "lane" comprised of the empty parking spaces. I think California Law is different, so people can have bike lanes.
Understood, I know the legalities vary from state to state. I was ranting about it purely based on etiquette. I’ve lived all over the US, and every area seemed to have a distinct traffic personality. I expected Bay Area traffic to be either very aggressive or very polite, but was surprised to find it best characterized as extreme rudeness via profound levels of incompetence and/or obliviousness to other drivers.
