43-310. Separate returns after filing joint returns
A. If a husband and wife have filed a joint return for a taxable year for which separate returns could have been made by them under section 43-309, and the time prescribed by this title for filing the return for such taxable year has expired, the spouses may nevertheless make separate returns for such taxable year. Separate returns filed by the spouses in such a case shall constitute their returns for such taxable year, and all payments, credits, refunds or other repayments made or allowed with respect to the joint return for such taxable year shall be taken into account in determining the extent to which the taxes based on the separate returns have been paid.
B. Separate returns may be filed under subsection A of this section only if there is paid in full all of the following, at or before the time of filing such returns:
1. All amounts previously assessed with respect to both spouses for such taxable year.
2. All amounts shown as the tax by the spouses upon their joint return for such taxable year.
3. Any amount determined, at the time of the filing of the separate returns, as a deficiency with respect to the spouses for such taxable year, if, prior to such filing, a notice of proposed deficiency under section 42-1108 has been mailed.
C. Separate returns may not be filed under subsection A of this section:
1. After the expiration of four years from the last date prescribed by this title for filing the return for such taxable year, determined without regard to any extension of time granted for the filing of the joint return.
2. After there has been mailed to the spouses, with respect to such taxable year, a notice of deficiency under section 42-1108, or if the spouses, as to such notice, appeal to the department under section 42-1251, or appeal to the state board under section 42-1253.
3. After the spouses have commenced a suit in court for the recovery of any part of the tax paid for the taxable year with respect to the joint return.
4. After the spouses have entered into a closing agreement under section 42-1113, with respect to such taxable year as to the tax payable by the spouse under their joint return.
D. If separate returns are made under subsection A of this section, any election, other than the election to file the joint return, made by the spouses in their joint return for such taxable year with respect to the treatment of any income, deduction or credit shall not be changed in the making of the separate returns where such election would have been irrevocable if the separate returns had not been filed.
E. If separate returns are made under subsection A of this section after the death of either spouse, such return with respect to the decedent may be made only by the decedent's personal representative.
F. Where the aggregate amount of the taxes shown by the spouses on their separate returns filed pursuant to subsection A of this section exceeds the tax shown on their joint return:
1. If any of such excess is attributable to negligence or intentional disregard of rules and regulations of the department, but without intent to defraud, at the time of making the joint return, then five per cent of the total amount of such excess on each return shall be assessed, collected and paid as if it were a deficiency.
2. If any part of such excess is attributable to fraud with intent to evade tax at the time of the making of the joint return, then fifty per cent of the total amount of such excess shall be so assessed, collected and paid, in lieu of the fifty per cent addition to the tax provided in section 42-1125.
G. For the purposes of section 42-1104, relating to periods of limitations upon assessment and collection, and for the purposes of section 42-1125, subsection A, relating to delinquent returns, separate returns made under this section shall be deemed to have been filed on the date on which the joint return was filed.
H. For the purposes of section 42-1118, relating to refunds and credits, separate returns made under this section shall be deemed to have been filed on the last date prescribed by this title for filing the return for such taxable year, determined without regard to any extension of time granted for the filing of the joint return.
I. If separate returns are made under subsection A of this section, the period of limitations provided in section 42-1104 on the making of assessments and collecting taxes shall, with respect to such returns, include one year immediately after the date of filing of such separate returns, computed without regard to the provisions of subsection G of this section.
J. For the purposes of section 42-1125, relating to penalties in the case of fraudulent returns, the term " return" includes a joint return filed by spouses with respect to a taxable year for which separate returns are made under subsection A of this section after the filing of such joint return.