Can we withhold a portion of our tenant's security deposit for the removal and repair to our roof from 2 dish satellites that were installed?

Question Details:

The roof had been completely redone the summer prior to the tenant moving in. The tenant had both Dish Network and Direct TV installed without the "prior written consent" from us. The tenant even asked us how having the satellites installed on the roof was an alteration to the house. We would never have given permission for this; we would have said that the installation could have been done in the ground surrounding the home. Important Notice