Damage Deposit withheld - consequences?

[Account Closed]

How often do you find tenants give you reason to withhold damage deposits? One of my mates, who also rents out properties, has a particularly nasty tenant who is leaving his building after many years. Little to no damage has been done to the flat, and small repairs have even been taken care of by the tenant. My mate plans on keeping the Deposit out of spite; what kinds of consequences should he anticipate facing from this action?