Ninja 250 Legality from state to state (Namely, California)??

I'm currently looking to purchase a ninja 250. While i currently reside in Arizona, I plan to move to California within a year or two. Someone told me that California has some sort of law/regulation that prevents me from purchasing a ninja here in AZ and then bringing it there. Perhaps some sort of smog/air quality thing? Im not sure... Is this true? What exactly is the law/regulation?