I learned a long time ago that ignorance of the law is no excuse when standing before a judge in a court of law. I also learned that our 50 states are in reality 50 individual countries with their own laws, and their own constitutions. When traveling from one state into another, one needs to keep track of those laws. One of the tools I use is:
http://drivinglaws.aaa.com/. It clearly states that when in California and towing, that the speed limit is 55 mph, unless you are in a area where the speed limit is posted as lower than 55 mph.
