[Blatt's] line of argument fell flat with at least three Justices – Scalia, Ginsburg, and Sotomayor – who throughout the argument generally regarded the case as covered by the plain language, even if not the purpose, of ICWA. Justice Elena Kagan’s vote was less certain, but she also seemed to at least be leaning that way: she pressed both Blatt and Deputy Solicitor General Ed Kneedler, representing the federal government as an amicus, to explain why, if Father is a “parent” for purposes of ICWA, he wouldn’t also be able to rely on the protections of Sections 1912(d) and (f). What, she asked Blatt, is the point of labeling Father as a “parent” if he doesn’t have any rights as such? Returning to this topic again later, Justice Kagan suggested that the Adoptive Couple’s construction of the law would effectively create two classes of parents under the statute – those with the protections provided in subsections (d) and (f), and those without. If Congress intended to do so, she queried, why didn’t it say so more explicitly?
At least three other Justices – the Chief Justice and Justices Breyer and Alito – seemed inclined to agree with Blatt and interpret ICWA more narrowly, particularly given what they clearly regarded as Baby Girl’s somewhat tenuous link to the Indian Tribe in question, the Cherokee Nation. Thus, the Chief Justice expressed some astonishment that “one drop of blood” could “trigger all these rights” under ICWA; both he and Justice Alito also tried to test the limits of the position taken by Charles Rothfeld, representing the Father, by asking him about a scenario in which the Tribe would allow virtually anyone to join the Tribe, regardless of whether the would-be members had any actual Indian ancestry. On this point, Justice Scalia chimed in to suggest that the hypothetical was a “null set” because there are federal criteria, including some blood relationship, that must be met for a Tribe to receive federal recognition. Rothfeld countered that in this case Father has significant ties to the Cherokee Nation, but in any event this is an issue that Congress or the executive branch can address.