In a document dated on his last workday as superintendent, Mr. Horne wrote that the Tucson program violated that statute — which did not take effect until two days later. Once it took effect, his successor, Mr. Huppenthal, hired an independent auditor to investigate the program.

In May 2011, the auditor reported that the program did not, in fact, violate A.R.S. 15-112 — at which point Mr. Huppenthal and other officials at the Arizona Department of Education opened their own investigation. Judge Tashima wrote that when the investigation began, the officials had already come to the conclusion that the program was illegal. Then, he found, the department conducted its inquiry solely on the basis of course materials, without attending any classes or speaking to any teachers.

Ultimately, Mr. Huppenthal directed the department to withhold 10 percent of the Tucson Unified School District’s state funding because of the violation of the statute, and the district decided to end the Mexican-American studies program as a result.

The court’s finding of racial animus relied primarily on anonymous blog comments posted by Mr. Huppenthal on political websites. On one occasion, he wrote: “No Spanish radio stations, no Spanish billboards, no Spanish TV stations, no Spanish newspapers. This is America, speak English.” On another, he wrote of the Tucson program: “The rejection of American values and embracement of the values of Mexico in La Raza classrooms is the rejection of success and embracement of failure.”