(1) If the federal taxable income of two taxpayers may legally be determined on a joint federal return but actually is determined on separate federal returns, such income for purposes of the Colorado income tax shall be separately determined.(2) If the federal taxable income of two taxpayers is determined on a joint federal return, their tax shall be determined on their joint federal taxable income.(3) Repealed.L. 87: Entire part R&RE, p. 1430, § 2, effective June 22. L. 88: (3) repealed, p. 1317, § 17, effective May 29. L. 2014: (1) and (2) amended, (SB 14-019), ch. 10, p. 98, § 3, effective February 27.(1) This section is similar to former § 39-22-109 as it existed prior to 1987.(2) Section 9 of chapter 10 (SB 14-019), Session Laws of Colorado 2014, provides that changes to this section by the act apply to income tax years commencing on or after January 1, 2013, and any other income tax years that are open under § 39-21-107 or 39-21-108.