My question involves a roommate in the State of: California
I signed a one year lease with my roommate in January 2009
We were both on the lease
I paid the deposit of $1100 and he gave me cash.
Rent was $1100 per month.
In September 2009, we decided to split ways.
There was a domestic fight. He said "I'm going to destroy your life" and proceeded to destroy and dispose of several hundred dollars worth of merchandise that I had made. This includes handmade costumes that cost near $100 each in supplies/materials and original artwork. The cost of the material he destroyed, in estimate, was well over $500. This does not factor in potential sale of these items which would be much more. Just basic costs of the materials they were constructed of.
He also reformatted my harddrive erasing all of my personal documents, records and artwork. This has no dollar value though.
We then negotiated with the landlord to end the lease one month early on November 1st.
The roommate found another apartment and moved out October 1st and refused to pay his last month of rent. $550.
Both of us were on the lease until November 1st.
I paid the full amount of October's rent on my own. $1100.
The landlord returned the full deposit to me.
This former roommate wants to sue me for his half of the deposit. $550.
Do I have legal standing to withhold his half of the deposit as payment for the last month of rent? And/or for the destroyed personal property?
I could probably sue him for the damaged property alone but I've been understanding of his situation and chose to let it go. It would easily amount to closer to $800 than the $550 he wants to sue me for.
thank you.

