The controversial approach of America's self-declared "toughest sheriff" have cost taxpayers in Arizona's most populous county some $51 million in compliance and legal fees, the Arizona Republic reported.

The hefty sum is the result of a 2007 lawsuit, in which Maricopa County's Joe Arpaio was found to have used racial profiling and was assigned a court-appointed monitor to make sure his office lives by a new set of rules, the newspaper explained.

"The tab for compliance with (U.S. District Court Judge Murray) Snow's orders is being paid directly by (county) taxpayers, right out of the general fund and the meter's still running," the Arizona Republic editorialized. "This, as Sheriff Joe Arpaio prepares to campaign for an astonishing sixth term next year."

Meanwhile, the expenses associated with the Melendres vs. Arpaio case are expected to grow by millions more in the coming years, the Associated Press noted.

"We have no idea what it's going to cost the taxpayers," Maricopa County Supervisor and Arpaio critic Steve Gallardo told the news service.

Mexican tourist Manuel de Jesús Ortega Melendres sued Arpaio after he had been stopped outside a Cave Creek, Arizona church that operated a day-labor center. Even though he was visiting the United States with a valid visa, Melendres was detained for hours, the Arizona Republic recalled.

Writing for the U.S. District Court for the District of Arizona, Snow eventually concluded that Arpaio's officers had systematically racially profiled Latinos in regular traffic and immigration patrols, according to the Associated Press.

He ordered changes and supervision that led the Sheriff's Office to purchase body cameras for hundreds of deputies; set up a computerized system aimed at detecting misconduct by officers; conduct additional training to make sure officers are not making unconstitutional traffic stops; and hire team of retired police officials to monitor Arpaio's office on behalf of the judge, the newswire detailed.

Tom Morrissey, a retired chief U.S. marshal and a longtime Arpaio friend, told the AP that lawsuits were inevitable for police officials who take a robust approach to law enforcement.

"If you aren't getting sued, you aren't doing your job," he suggested.