There are times when Sheriff Joe Arpaio has seemed untouchable. In his nearly 20 years in office, he has survived political challenges, court judgments and criminal investigations.

But a ruling filed last week by an arm of the Arizona Supreme Court could prove to be a road map to the Republican lawman’s undoing.

A three-person disciplinary panel of the state’s high court said there was enough evidence to prove “beyond a reasonable doubt” that the sheriff and three of his closest allies participated in what the panel believes was federal crime in December 2009.

The alleged crime doesn’t stem from battles over immigration, pink underwear or any of the other things that have made Arpaio famous. Instead, it deals with a feud among local government officials in which the panel said the sheriff and his allies took things way too far.

The ruling was the result of almost two years of investigation by the State Bar of Arizona as well as two months of sworn testimony, including from Arpaio himself, in front of the Supreme Court’s disciplinary panel last year.

h/t: Nick R. Martin at TPM