If the roommate can prove your boyfriend was negligent by leaving the window open, then yes, he can be held responsible for the damages suffered. The hobo would also be liable, but getting any money from him is most likely impossible. The key is the roommate would have to prove the window was left unlocked. If it was, then your boyfriend may just want to pay the $500 if the damages were more. Or he can negotiate the amount. If he does pay, make sure he has the other party sign a release stating that the payment is infull settlement of all claims, to ensure the do not continue to come back for more money later. Good luck.
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