Navigating the complexities of tax law can be difficult, especially when faced with an unexpected tax bill due to the errors of a spouse or ex-spouse. The reason for such a bill has to do with the concept of “joint and several” liability. When a married couple files a joint tax return, each spouse is liable for the full amount of tax on the couple’s combined income. Therefore, the IRS can come after either spouse to collect the entire tax — not just the part that’s attributed to one spouse or the other. This includes any tax deficiency that the IRS assesses after an audit, as well as any penalties and interest. There may be relief In some cases, spouses are eligible for “innocent spouse relief.” This...