Thomas said his office is considering "lawful options" to end required participation in the Superior Court's DUI court for Spanish-speakers and American Indians.
Thomas pulled a staff member this year from a committee organizing a court for the homeless that Tempe and Phoenix municipal courts will begin operating in February.
Pearce, R-Mesa, head of a House Appropriations Committee, said he'll withhold funds if necessary to end them.
Thomas and Pearce say creating courts based on race, language and socioeconomic status is unconstitutional.
Presiding Judge Barbara Rodriguez Mundell, who oversees Maricopa County Superior Court and the county's lower courts, said the special courts are constitutional, and Thomas doesn't understand how they operate.
"We did our research to make sure this is constitutional," Mundell said.
The Spanish-speaking and American Indian DUI courts were begun in 2002, before Thomas was elected. They are funded by a federal grant.
The courts are rehabilitation programs for felony DUI offenders on probation, said Mundell, who handles the Spanish-speaking court.
The state Constitution requires that courts of record, those where a record of every spoken and written word is kept, do business in English.
But once a Spanish-speaker is convicted and joins the program, the proceedings are no longer "of record"; just simply monthly status conferences on the person's rehabilitation progress, Mundell said.
