Our colleague Elizabeth Dias files this report:

If you’ve followed the illegal immigration controversy in Arizona, you’ll be familiar with the state’s hard-edged Sheriff Joe Arpaio, who is famous for dressing inmates in pink underwear and for boasting an all-female chain gang. Loved by conservatives, hated by immigrant-rights groups, Arpaio is now in the news for an alleged threat on his life. He’s been making the media rounds claiming a Mexican drug cartel has put a $1 million price on his head via a text message tree.

Some people are skeptical, as Arpaio is known for his constant appetite for publicity. (Even though he is not up for election this year, he is running a re-election ad.) Cartels are an Arizona hot-button, but they have not been a primary target of Arpaio’s. In the past few years his office has arrested 35,889 undocumented immigrants, compared with only 303 “coyotes,” the popular name for operators of human-smuggling rings. No one has publicly confirmed that the threat is actually from a cartel, and no information has been released on how the cartel phone number was traced, but sheriff’s-department officials say the threat originated from a Mexican throw-away phone.

The death threat isn’t the only controversy swirling around Arpaio. The U.S. Justice Department has been investigating the controversial Arizona sheriff since March 2009, when Phoenix Mayor Phil Gordon wrote to the DOJ accusing Arpaio of “a pattern and practice of conduct that includes discriminatory harassment, improper stops, searches and arrests.” That same month, officers booked an undocumented Hispanic woman on false identification charges, tried to force her fingerprint on a voluntary removal order, and broke her arm in the process. (The false-identification charges proved inaccurate.)

This week the DOJ gave Arpaio an ultimatum: hand over the documents requested last year for alleged racial discrimination charges, or be sued. Claiming that Arpaio has provided all the requested Title VI documents, Robert Driscoll, Arpaio’s attorney, told Fox News that racial profiling charges won’t stand on Arpaio: “Could there be a police operation that is more transparent than Sheriff Arpaio’s office?” he said. And yet, Arpaio’s office admitted in February to destroying records and office emails about his crime sweeps.

But while Arpaio has kept the focus on the death threat rather than the DOJ suit, he has not asked the FBI to help investigate the threat. Nor has Arpaio’s office asked T-Mobile, the carrier of a phone that received the threat, for any assistance tracking its origin. Patty Raz, T-Mobile spokeswoman, said TIME was the first to bring this issue to T-Mobile’s attention and that T-Mobile has received no requests from any law enforcement agency on this issue. “We would work with them if they contacted us, of course,” Raz said.