John R. Dorocak (California State University, San Bernardino) has published Recent Constitutional Questions in Taxation: Toward a Legislative Solution to Constitutional Problems of Same-Sex Couples and Ministers of the Gospel?, 19 Temp. Pol. & Civ. Rts. L. Rev. 223 (2009). Here is the part of the Introduction:

This Article reviews two different constitutional questions regarding federal income taxes. First, the constitutionality of the income tax exclusion of the housing allowance for ministers of the gospel under the Establishment and Free Exercise Clauses of the First Amendment is discussed. Second, [the] constitutionality, under the Due Process and Equal Protection Clauses of federal and state constitutions' denial of various tax benefits, such as joint filing for married couples is examined. …

The exclusion from income taxation of the parsonage, or housing allowance, for “ministers of the gospel” under § 107 has raised First Amendment questions regarding establishment of religion and/or the free exercise thereof. The tax filing status of same-sex couples, whether as head of household or married filing jointly, has raised constitutional questions of at least due process, equal protection, and full faith and credit. This Article will first examine the constitutional questions raised in the “minister of the gospel” housing allowance, particularly as posed by the leading case, Warren v. Commissioner, and the relative silence on this issue since congressional action taken in May 2002. Second, this Article will reexamine the constitutional questions of same-sex couples in the tax context in a seemingly ever-evolving area. Third, this Article will seek to explore the differences between the resolution of the constitutional questions regarding the ministers of the gospel housing allowance versus the ongoing and unanswered constitutional questions for same-sex couples. By examining these two areas of constitutional questions in the tax field, some light might be shed on resolving as-yet unsettled questions.