If you exited the freeway, you obeyed the sign. There are no signs whatsoever stating that you can't re-enter 101 again. You did nothing wrong. Obtain a copy of officer's statement from the court, and that should provide more clarity. But you should definitely challenge this by Trial de Novo. Make sure you bring plenty of Googla Maps printouts so that the judge is absolutely clear that you did exit the freeway. Make sure it's a different judge from the one who convicted you in TBD. If it is the same one, raise a peremptory challenge as per CCP 170.6 , on the grounds you don't believe you can get a fair trial.