I have a vehicle that isn't in my name can I file for a car registration fee deduction

For you to be able to take a deduction for taxes paid for the car registration fee, you must have this fee imposed upon you personally and have the obligation to pay it due to a "legal" interest in the vehicle. If the vehicle is in another person's name, then the other person bears the legal responsibility for the vehicle to have proper registration, etc for the vehicle to be legally driven on the road. In addition, the other person is the true owner of the vehicle.

What if the car is in the name of someone who is my dependent? Since they didn't (couldn't?) claim it in their return, and since I am the one paying for their living expenses, would I be able claim the deduction in that case?

 In order to claim the fee two criteria must be met.

 1) You must be legally obligated to pay it.

 2) You must have actually paid it.

If you don't meet both requirements, you can't claim it.