Here.

In this case, the GAL petitioned to remove the child from the mother’s care. This GAL has considerable issues with the application of ICWA:

The GAL argued that since ICWA does not explicitly
define what qualifies a witness as an expert, the juvenile
court had “discretion to determine whether a witness has
adequate qualifications to provide the proffered testimony.” Although the three therapists were not qualified to testify regarding tribal cultural standards, the GAL asserted that the court was not bound by the BIA regulations and urged the court to qualify the therapists as expert witnesses anyway . . .

The Court of Appeals instead agreed with mother and Tribe, stating:

Therefore, because the BIA is a federal administrative agency and ICWA is a federal statute, we must employ the principles articulated in Chevron to determine whether the BIA’s 2016 regulation defining “qualified expert witness” is entitled to deference.

***
Determining that a “qualified expert witness” “should be qualified to testify as to the prevailing social and cultural standards of the Indian child’s Tribe” is consistent with Congressional intent and is reasonable.

Unfortunately, the appellate court ultimately held that:

Although the juvenile court correctly applied Chevron
deference to the BIA’s interpretation of ICWA, it did not
correctly apply the regulation, because it rejected the GAL’s experts solely on the ground that they were not qualified to testify regarding the Tribe’s cultural standards without considering whether those standards had any actual bearing on the proposed grounds for removal. Further, the juvenile court erred in determining that Mother could claim therapist–patient privilege with respect to testimony from her therapist and the family therapist. We therefore reverse the juvenile court’s decision and remand for further proceedings consistent with this opinion.