Innocent spouse relief is available for understatement of income on a jointly filed tax return. However, it is not available in cases where a joint return was filed with a correct tax liability and the taxes were unpaid.
In other words, if you and your spouse filed a joint return and all the information was correct – you cannot request innocent spouse relief if no taxes were enclosed with your joint tax return. This is known as failure to pay taxes. You two will be penalized.