The reason I attributed it to "liberalism" wasn't due to its institution by a Repuclican or Democratic local administation, but instead, seeing the effort couched in "its good for you" terms as well as expanding the pervasiveness of government made it fit in that category in my mind. Planned outcomes are so much part-and-parcel to that mindset.
If it had been more along the lines of a policy to stop all teen drivers for general checks, then I would see it as a Right-wing, stateist expansion of government issue, but the Nanny State tone of the policy was the deciding factor.
Welcome. I hope we can trade opinions on something more important the next time.