Section 1.1312-4 - Double disallowance of a deduction or credit(a) Paragraph (4) of section 1312 applies if the determination disallows a deduction or credit which should have been, but was not, allowed to the same taxpayer for another taxable year or to a related taxpayer for the same or another taxable year. This is one of the two circumstances in which the maintenance of an inconsistent position is not a requirement for an adjustment but the requirements in paragraph (b) of § 1.1311(b)-2 must be fulfilled (correction not barred at time of erroneous action).(b) The application of paragraph (a) of this section may be illustrated by the following examples: Example 1. The taxpayer, A, who computes his income by use of the accrual method of accounting, deducted in his return for the taxable year 1951 an item of expense which he paid in such year. At the time A filed his return for 1951, the statute of limitations for 1950 had not expired. Subsequently, the Commissioner asserted a deficiency for 1951 based on the position that the liability for such expense should have been accrued for the taxable year 1950. In 1955, after the period of limitations on refunds for 1950 had expired, there was a determination by the Tax Court disallowing such deduction for the taxable year 1951. A is entitled to an adjustment for the taxable year 1950. However, if such liability should have been accrued for the taxable year 1946 instead of 1950, A would not be entitled to an adjustment, if a credit or refund with respect to 1946 was already barred when he deducted such expense for the taxable year 1951.Example 2. The taxpayer, B, in his return for 1951 claimed a deduction for a charitable contribution. The Commissioner asserted a deficiency for such year contending that 50 percent of the deduction should be disallowed, since the contribution was made from community property 50 percent of which was attributable to B's spouse. The deficiency is sustained by the Tax Court in 1956, subsequent to the period of limitations within which B's spouse could claim a refund with respect to 1951. An adjustment is permitted to B's spouse, a related taxpayer, since a refund attributable to a deduction by her of such contribution was not barred when B claimed the deduction.T.D. 6500, 25 FR 12034, Nov. 26, 1960