Edelglass v. State of N.J., 2015 U.S. Dist. LEXIS 5320 (D.N.J. Jan. 16, 2015):

The domestic relations [*24]  exception to federal diversity jurisdiction was first raised in Barber v. Barber, 21 How. 582, 16 L. Ed. 226 (1859). In 1992, the Supreme Court explained that the domestic relations exception, as applied by the federal courts since Barber, "divests the federal courts of power to issue divorce, alimony, and child custody decrees." Ankenbrandt v. Richards, 504 U.S. 689, 703 (1992). More recently, the Supreme Court acknowledged that "it might be appropriate for the federal courts to decline to hear a case involving elements of the domestic relationship, even when divorce, alimony, or child custody is not strictly at issue: This would be so when a case presents difficult questions of state law bearing on policy problems of substantial public import whose importance transcends the result in the case then at bar." Elk Grove Unified Sch. Dist. v. Newdow, 542 U.S. 1, 13 (2004) (internal quotation marks and citations omitted). However, the Supreme Court further stated that "rare instances arise in which it is necessary to answer a substantial federal question that transcends or exists apart from the family law issue, see, e.g., Palmore v. Sidoti, 466 U.S. 429, 432-434, (1984), [though] in general it is appropriate for the federal courts to leave delicate issues of domestic relations to the state courts." Id.

There is a split among the Circuit Courts of Appeal as to whether the domestic relations exception [*25]  applies only to cases brought under diversity jurisdiction or to any case that would otherwise have federal subject matter jurisdiction. See Meredith Johnson Harbach, Is the Family a Federal Question?, 66 Wash. & Lee. L. Rev. 131, 147 (2009) (noting circuit split and listing cases). However, the Third Circuit has limited the domestic relations exception to diversity: "'as a jurisdictional bar, the domestic relations exception does not apply to cases arising under the Constitution or laws of the United States.'" McLaughlin v. Pernsley, 876 F.2d 308, 312 (3d Cir. 1989) (quoting Flood v. Braaten, 727 F.2d 303, 308 (3d Cir. 1984)).