Deposit question

[William R.]

This is a question from a friend,so I don't have all the details. Their tenant claimed the apartment was unbearably loud from other tenants, so the owner tried adding carpet in the unit above, enforced quiet hours etc. The tenant insisted on moving out, so the owner agreed to let them out of their lease without having them sign anything. They moved out a few days late and caused a bit of damage. A new lease has been signed for 15 days after the move out. Can the owner subtract the lost rent for those 15 days from the deposit? Or, are they obligated to return the deposit at all? The tenant is threatening small claims court unless the full deposit is returned minus the damage.