- 19 - per curiam 540 F.2d 821 (5th Cir. 1976). As relevant herein, section 6662(a) imposes an accuracy- related penalty equal to 20-percent of an underpayment that is due to a substantial understatement of income tax. See sec. 6662(a) and (b)(2). An individual substantially understates his or her income tax when the reported tax is understated by the greater of 10-percent of the tax required to be shown on the return or $5,000. Sec. 6662(d)(1)(A). Tax is not understated to the extent that the treatment of the item is (1) based on substantial authority, or (2) relevant facts are adequately disclosed in the return or in a statement attached to the return and there is a reasonable basis for the tax treatment of such item by the taxpayer. Sec. 6662(d)(2)(B). Moreover, the accuracy-related penalty does not apply with respect to any portion of an underpayment if it is shown that there was reasonable cause for such portion and that the taxpayer acted in good faith with respect to such portion. Sec. 6664(c)(1). The determination of whether a taxpayer acted with reasonable cause and in good faith is made on a case-by-case basis, taking into account all the pertinent facts and circumstances. Sec. 1.6664-4(b)(1), Income Tax Regs. The most important factor is the extent of the taxpayer’s effort to assess the taxpayer’s proper tax liability for such year. Id. Petitioner reported zero tax on his 1998 return. The amountPage: Previous 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Next
Last modified: May 25, 2011