Story highlights Courses were "biased, political, and emotionally charged," a state official rules

The finding could cost Tucson schools $15 million a year

A 2010 Arizona law bars classes that promote "racial resentment" or "ethnic solidarity"

An earlier audit found the classes didn't violate that law

Public schools in Tucson, Arizona, face millions of dollars in penalties after a ruling that the district's Mexican-American studies program violates state law.

An administrative law judge found the program's curriculum was teaching Latino history and culture "in a biased, political, and emotionally charged manner," and upheld state officials' findings that it violated a state law passed in 2010. The Tucson Unified School District had appealed a decision by the law's principal backer, then-state schools superintendent Tom Horne, to shut down the program.

Horne left office at the end of 2010, but his successor, John Huppenthal, backed Horne's ruling in June. Huppenthal said Tuesday's ruling shows "that it was the right decision."

"In the end, I made a decision based on the totality of the information and facts gathered during my investigation -- a decision that I felt was best for all students in the Tucson Unified School District," he said in a written statement.

Under the law, the state can withhold 10% of its funding for the school district -- about $15 million a year -- until the district changes the course. In a written statement, Tucson Superintendent John Pedicone said the school board's lawyers are reviewing the ruling, and board members will discuss it at their January 3 meeting.

During their appeal, district officials pointed out that an audit commissioned by Huppenthal praised the program and found "no observable evidence" that the classes violated state law.

A witness for the school system argued that teaching students "historical facts of oppression and racism" was less likely to promote "racial resentment" -- something specifically banned by the 2010 law -- than ignoring that history.

In Tuesday's ruling, administrative law judge Lewis Kowal said the auditors observed only a limited number of classes. He added, "Teaching oppression objectively is quite different than actively presenting material in a biased, political, and emotionally charged manner."

"Teaching in such a manner promotes social or political activism against the white people, promotes racial resentment, and advocates ethnic solidarity, instead of treating pupils as individuals," Kowal wrote. He cited a lesson that taught students that the historic treatment of Mexican-Americans was "marked by the use of force, fraud and exploitation," and a parent's complaint that one of her daughters, who was white, was shunned by Latino classmates after a government course was taught "in an extremely biased manner."

The 2010 law also bans courses that "promote the overthrow of the United States government," are "designed for a specific ethnic group" or advocate "ethnic solidarity instead of the treatment of pupils as individuals." It was passed in the same session of the state legislature that produced Arizona's controversial law cracking down on illegal immigration.

A group of teachers has asked a federal court to throw out the restrictions, arguing they passed as "a result of racial bias and anti-Hispanic beliefs and sentiments." Richard Martinez, the lawyer who represents the teachers in that case, said the decision was expected "under the circumstances."

"The law was written in a way that allows the superintendent of public instruction to control the outcome," Martinez told CNN. And Kowal noted that he was working under the assumption that the law is constitutional, "ignoring any questions raised" to the contrary, Martinez said.