To the best of my knowledge, every professional baseball player has to sign an agreement with a laundry list of "no can do's". I'm sure speeding/reckless driving is on that list. The dodgers should take the appropriate action as it applies to the agreement.
Baseball is a business, and just like any other business it has to discipline its employees. At some point, the business has to decide if keeping an employee that breaks the rules is worth the risk.
My guess, based on his talent, that he will get a few more chances to grow up. But, at some point, continued bad behavior will effect the business.
GO GIANTS!