Sheriff Joe Arpaio, the hard-line anti-immigration Arizona sheriff, is being probed by the FBI for allegedly using his authority to retaliate against political adversaries, sources tell a local TV station. One of the key cases cited by Phoenix-based KPHO is one we told you about recently, in which a husband-and-wife team of big-name Washington GOP lawyers was briefly recruited to try to build a case against a local official who had clashed with Arpaio.

In response to the KPHO report, Arpaio bizarrely lashed out at ... David Iglesias, the former U.S. attorney who had dared offer an expert opinion to the station.

Arpaio -- the Maricopa County sheriff who has used press-friendly stunts like forcing prisoners to wear pink underwear to build a national reputation -- recently had his authority to conduct immigration raids scaled back by the Justice Department.

But the reported FBI probe could turn into a far bigger headache. KPHO reports that it has examined more than two dozen complaints against the sheriff from business owners, government workers, mayors and law-enforcement officials, who allege that after they spoke out against Arpaio, they found themselves the subject of investigations by his office -- none of which have resulted in convictions, and many of which never even led to charges being filed.

KPHO cites numerous such cases, many of which have made local headlines in the past. But one prominent one is that of Don Stapley, the county supervisor who, after pushing for audits of Arpaio's office, found himself arrested by sheriff's deputies in September. The sheriff's office has alleged violations of campaign-finance laws, but no prosecutor has taken the case. And last week, county officials short-circuited an effort to turn it over to Washington GOP power couple Joseph diGenova and Victoria Toensing.

In an interview with TPMmuckraker, Stapley's lawyer, Paul Charlton, compared Arpaio's modus operandi , as laid out by KPHO, to that of an eastern European dictator who deals with dissent by having outspoken citizens shot, so as to warn others not to speak up. "If it were one or two events, you could say this was an aberration," Charlton said. "But when it's repeated over time ... this was an attempt to intimidate them."

Charlton knows something about missteps in the administration of justice. He was one of the U.S. attorneys who was improperly fired by the Bush administration, after irritating DOJ officials by arguing against the death penalty in one case.

And remarkably, another of those fired U.S. attorneys also now finds himself tangled up in the case -- as a target of Arpaio's retaliatory tactics. As an independent expert who could assess KPHO's research on Arpaio, the news station had turned to David Iglesias, who famously was dismissed as the top federal prosecutor in New Mexico by declining to bring politically motivated prosecutions sought by the state's GOP.

Iglesias, who has never met Arpaio, told KPHO that if he were handling the case, he would "seek an indictment."

Saying he had never seen anything like it in his long career in law enforcement, Iglesias called Arpaio's actions "absolutely unacceptable," adding, "we don't do this kind of thing in America ... without some kind of consequences."

In response, Arpaio went after Iglesias, releasing a statement through his office that tried to tie the former Navy JAG to the right's latest bete noir:

Iglesias was criticized for looking the other way in an investigation involving ACORN, an organization that embraces illegal immigration and is currently under intense scrutiny and investigation by the US government for fraudulent schemes.

The statement also clumsily attacked Charlton as an "impartial (sic) and bias (sic) observer of the facts."

Other cases cited by KPHO of Arpaio using the sheriff's office to go after critics include those of:

• Phil Gordon, the mayor of Phoenix, who last year asked DOJ to investigate complaints of racial profiling against the Arpaio's office, then received demands from the sheriff's deputies for copies of all of Gordon's e-mail, phone logs and appointment calendars. Gordon told KPHO the effort "definitely was" retaliatory.

• And Daniel Pochoda, a local ACLU lawyer who was arrested by Arpaio's deputies for trespassing at a 2007 anti-Arpaio demonstration, and found not guilty last year.

• Terry Goddard, the Arizona attorney general, who had criticized Arpaio's use of resources to arrest otherwise law-abiding illegal immigrants, rather than focusing on those with outstanding warrants. In 2007, Arpaio's office began a probe into a payment made by the state treasurer's office to Goddard's office -- but no charges have yet been filed.

Arpaio, a Republican, has expressed interest in a run for governor next year, where he could face Goddard, a Democrat.