Joe Arpaio, the sheriff of Maricopa County, Arizona, walked onto the stage at the Republican National Convention in Cleveland, a few hours before Donald Trump was supposed to deliver his acceptance speech. Arpaio, a tough-on-illegal-immigration crusader, flashed a peace sign as the crowd roared its approval. Wearing an oversize black suit and a tie pin in the shape of a pistol, the 84-year-old sheriff said he's spent 55 years in law enforcement, but his "most important mission has just begun: to help elect Donald Trump president of the United States." Trump is the only candidate strong enough to defend the nation from "terrorists coming over our border, infiltrating our communities and causing massive destruction and mayhem," he said, adding that "criminals [are] penetrating our weak border security system and committing serious crime." Arpaio earned his spot on the RNC stage by styling himself as "America's Toughest Sheriff," who famously stops immigrants for no reason, dresses jail inmates in pink underwear, and houses the inmates in Korean War tents in the desert heat.