Driveway rights in lease

[Kaleigh Griffiths]

I have a multi-level building in SF with multiple units. It has a lower level two-car garage with a single-car driveway. The two bottom units pay for and have access to the garage in order to park. I did not give the top unit a key to the garage, nor do they have parking rights in the lease. However, the top unit claims that they have equal driveway access, and call the police on the bottom tenants whenever their cars are blocking the driveway. Do they have the right to do this even though they do not have garage access or permission to park there in their lease? I have received multiple complaints of this nature about the top tenants for the past couple years and because I rent in a student area, it is starting to deter people from renting my units.