The Tax Court yesterday held that § 152(e)‘s assignment of the dependency exemption to the custodial parent unless the custodial parent releases his or her right to the exemption in writing does not violate the equal protection rights of non-custodial parents who provide more than half of a child’s support:

Prior to 1984, a noncustodial parent could claim a dependency exemption pursuant to § 152(e) if he or she provided $1,200 or more for the support of a child and the custodial parent could not clearly establish that he or she provided more support than the noncustodial parent. This provision required the IRS to wade into disputes between parents “who both [claimed] the dependency exemption based on providing support over the applicable thresholds.” H. Rept. 98-432 (Part 1), at 197 (1984). Thus, Congress added the written declaration requirement to § 152(e) to eliminate the role of the IRS as mediator between divorced or separated parents, provide more certainty to the “often subjective and * * * difficult problems of proof and substantiation” that accompanied dependency exemption disputes, and clarify which of two divorced parents would receive the dependency exemption. [Citations omitted.]  Because § 152(e) eases the administrative burden of the IRS and thereby advances enforcement of the statute in a rational way, it furthers a legitimate congressional purpose. Therefore, § 152(e) does not violate the Due Process Clause of the Fifth Amendment to the Constitution of the United States. Accordingly, we hold that petitioner is not eligible for a dependency exemption or a child tax credit for the taxable year 2003.

Harris v. Commissioner, T.C. Memo. 2007-239 (8/22/07).