Maricopa County Attorney Andrew Thomas is asking the state Supreme Court to restore some of his duties.
In a "petition for special action," Thomas asked the high court Friday to abolish a relatively new civil-litigation unit the county Board of Supervisors created late last year.
Thomas says supervisors have broken the law by creating an additional legal office that has "unlawfully usurped" his authority as the county's legal adviser.
Thomas and the Board have been at odds since early December, after Thomas' office indicted Supervisor Don Stapley on 118 criminal counts alleging he failed to disclose property and real-estate deals over the course of 14 years.
Stapley has denied the charges and nearly half of the charges have been thrown out,.
Following the indictment, supervisors claimed Thomas had a conflict of interest, ousted him as their legal adviser and created a new in-house civil legal department.