I am a long term tenant and the original lessor of my apartment, and paid the full security deposit at move in. I've had roommates over the years, and as they have moved in and out, they have written me a check for "their share" of the deposit, and upon move out, I have refunded it. Never had a problem, until now.
A fairly long-term (3+ years) roommate of mine moved out recently. We were both on the lease, and when he moved in, he wrote me a check for his share of the security deposit. Over the course of his tenancy, he damaged and broke personal items of mine that exceed the amount of the security deposit, and reach into the hundreds of dollars. Finally, I asked him to move, and he continued to break and damage things. I have documentation of the damages caused. He has admitted to some, but not all of the damages caused.
I refused to return the deposit, and sent him a letter to that effect, detailing each of the damaged/destroyed items very soon after he vacated.
I am in MN. Is it legal to withhold his portion of the security deposit for damage to personal items? If not, what course of action would you recommend? Any help you could provide would be much appreciated.

