It seems that the case law cited by "Take the CHP to Court!" is hardly decisive. If I were to believe that non-decision, it means that every demonstration on any street, not just overpasses, is potentially subject to the same restrictions and potential litigation under state law. The deciding factor seems to be to demonstrate, after the fact, just how much traffic congestion was actually caused by the demonstration. According to the exact words of the decision, I guess one could argue that the freeway overpasses themselves are not freeways and therefore not subject to Cal-Trans jurisdiction? Maybe. Certainly one would not be restricted in the same way from displaying a sign or signs held up along a frontage road, such as Soquel Avenue between the Soquel Exit and 41st Avenue? Also, bumper stickers and huge signs on busses and truck trailers are not restricted. That's it. Arrest Robert Norse for driving on highway 1 with a car covered with bumper stickers that has not been approved by Cal-Trans. I smell an as applied challenge. It would be expensive though.