Justice Neil Gorsuch again highlighted the mistreatment of tribal communities by the federal government in a U.S. Supreme Court decision Thursday, saying Justice Brett Kavanaugh’s majority opinion “neglects” the circumstances that led to an 1868 water-rights treaty involving the Navajo Nation.

The Supreme Court ruled 5-4 that the U.S. government is not required to take “affirmative steps to secure water” for the Navajo Nation from the Colorado River under the treaty. That accord implicitly includes water rights for the tribe on its 17 million-acre reservation but does not impose any “duty” on the United States to actively secure those rights, Kavanaugh wrote.