My 80 year old condo tenant signed a lease that ends in March 2010. He has been hospitalized and will be going straight to a nursing home. The tenant previously gave me signed notice that he will vacate the premises effective July 1. His 50 year old son had also moved into the condo, and he refuses to leave or pay the July rent. Do I need to go through the eviction process to get him out or is the son trespassing so I can just call the police? The son is not on the lease.

He can't be considered trespassing. You have to go through the eviction process.