Since the checking account is in both of our
names can I legally use the money from the
refund when it hits the account to pay our
bills even though the refund isnt mine.
I disagree with the others on this one. While the bank will let you take the money from the bank account, and doing so likely won't be a crime, if the deal was that it's his money then he could sue you to get it back if you take it. Similarly, though, you can sue him for taking out funds that the two of you agreed belonged to you. It reallly comes down to what the deal was between you. At least claiming the funds would give you a leg up in the matter; you could set it aside until all the disputes were settled and you'd at least have it if you ultimately prevail.