Opinion of the Court
B
This case arises from three separate child custody proceedings governed by ICWA.
1
A. L. M. was placed in foster care with Chad and Jennifer Brackeen when he was 10 months old. Because his biological mother is a member of the Navajo Nation and his biological father is a member of the Cherokee Nation, he falls within ICWA’s definition of an “Indian child.” Both the Brackeens and A. L. M.’s biological parents live in Texas.
After A. L. M. had lived with the Brackeens for more than a year, they sought to adopt him. A. L. M.’s biological mother, father, and grandmother all supported the adoption. The Navajo and Cherokee Nations did not. Pursuant to an agreement between the Tribes, the Navajo Nation designated A. L. M. as a member and informed the state court that it had located a potential alternative placement with nonrelative tribal members living in New Mexico. ICWA’s placement preferences ranked the proposed Navajo family ahead of non-Indian families like the Brackeens. See §1915(a).
The Brackeens tried to convince the state court that there was “good cause” to deviate from ICWA’s preferences. They presented favorable testimony from A. L. M.’s court-appointed guardian and from a psychological expert who described the strong emotional bond between A. L. M. and his foster parents. A. L. M.’s biological parents and grandmother also testified, urging the court to allow A. L. M. to remain with the Brackeens, “ ‘the only parents [A. L. M.] knows.’ ” App. 96.
The court denied the adoption petition, and the Texas Department of Family and Protective Services announced its intention to move A. L. M. from the Brackeens’ home to New Mexico. In response, the Brackeens obtained an emer-
