A. Notwithstanding section 43-301, subsection C and section 43-562, after filing a joint income tax return pursuant to section 43-309, a taxpayer may seek relief from joint and several liability under the following circumstances:

1. 1. There is an understatement of tax attributable to erroneous items of one of the taxpayers filing the joint return.
2. 2. The taxpayer making an election under this section establishes that in signing the return the taxpayer did not know, and had no reason to know, that there was an understatement.
3. 3. Taking into account all of the facts and circumstances, it is inequitable to hold that taxpayer liable for the deficiency attributable to the understatement.