From the abstract:
Confusion over the applicability of marital privileges invoked by same-sex spouses from one jurisdiction to the next has a chilling effect on the full and frank communication marital privileges seek to encourage. With the growing number of jurisdictions recognizing same-sex marriages in the wake of United States v. Windsor, conflicts between state marriage laws embracing marriage equality and state versions of the Defense of Marriage Act (“mini-DOMAs”) will similarly increase. Section 2 of the Defense of Marriage Act (“DOMA”) permits a state with a mini-DOMA to invalidate a marriage validly celebrated in another. So, too, may a state with a mini-DOMA refuse to recognize a marital privilege otherwise available to opposite-sex couples to protect a same-sex marriage celebrated in another state or a confidential communication held in another state. A conversation in New York, which would recognize a valid marriage between same-sex partners and thus apply any available marital privilege, may never be had for fear that future litigation in Texas, which maintains a mini-DOMA, may force one spouse to reveal those confidential communications while testifying adversely to her spouse.
To provide the certainty needed to fulfill the purpose of the marital privileges, federal court intervention is required to strike section 2 of DOMA and all mini-DOMAs as unconstitutional violations of the Equal Protection Clause of the Fifth and Fourteenth Amendments, as well as the Full Faith and Credit Clause of the Fourteenth Amendment. With reasonable certainty that their marriages will be deemed valid in all jurisdictions, same-sex couples can take comfort in knowing they will not be forced to testify adversely to one another or reveal confidential communications they shared. Same-sex marriages, like their opposite-sex counterparts, will be strengthened by the benefits such privileges afford.