His critics say he has a long history of launching bogus criminal investigations against political opponents and anyone else who gets in his way.
He was the subject of a civil lawsuit by the Justice Department alleging civil rights violations. According to the complaint, the sheriff's office has displayed a pattern of discrimination against Latinos that includes racial profiling, unlawful detention and searches, and unlawful targeting of Latinos during raids.
Arpaio has denied any discrimination, and one of his attorneys called the Justice Department investigation a "witch hunt."
His office website touts his "get tough" policies and says his chain gangs contribute thousands of dollars of free labor to the community. Male chain gangs, as well as the world's first-ever female and juvenile chain gangs, clean streets, paint over graffiti and bury the indigent in the county cemetery.
After winning his sixth term last November, the 80-year-old sheriff said he doesn't plan on leaving office anytime soon.
"For my critics out there, I'm going to say right now: In January, I'm signing up for 2016. So I'm not a lame duck," he told a crowd of cheering supporters.