Yes, you can. While the IRS may allow him to avoid having to pay under innocent spouse relief, that does not change the state court's order in the MSA. If the agreement when the decree was entered was that the parties divide the debts then you may prevail so long as you can establish that the tax debt is joint. However the innocent spouse designation will likely be used by his attorney as a defense. So you'll have to prove the point to prevail. You'll definitely want to consult with an attorney and get some competent representation on this one.
Yes, I agree. You should understand that the IRS is not required to follow the MSA, although they are supposed to give due consideration. A contempt charge could possibly be filed in the family court of jurisdiction for violation of the MSA.
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