DOJ has been looking into whether Arpaio is in violation of Title VI of the Civil Rights Act since March 2009. The controversial Arpaio passed a deadline last month to provide DOJ with the documents they requested, and his lawyer met with DOJ last week.
The Justice Department said at the time it was "hopeful" that Arpaio would cooperate following the meeting, but in a statement said on Thursday that it had "[exhausted] all cooperative measures" to gain access to the requested documents and facilities.
DOJ is unaware of any other police department of sheriff's office that has refused to cooperate with an investigation in the past 30 years, making Maricopa County "an extreme outlier," said the department.
"The actions of the sheriff's office are unprecedented. It is unfortunate that the department was forced to resort to litigation to gain access to public documents and facilities," Thomas E. Perez, Assistant Attorney General for the Civil Rights Division, said in a statement.
Arpaio's lawyer Robert Driscoll, when reached by TPM, said he was still reviewing the filing and had no comment.
Late Update: Arpaio has responded to the federal lawsuit, saying he was disappointed to hear of the suit because he thought they were close to resolving the issue.
"I'm not going to be intimidated by the federal government going to court against us," Arpaio said.
DOJ's lawsuit is embedded below.