President Barack Obama is expected to nominate Assistant Attorney General Thomas Perez to be his new labor secretary, and though the pick isn't official yet, conservatives are already assailing the choice.

The backlash comes on the heels of the contentious debate that preceded Defense Secretary Chuck Hagel's confirmation, when lawmakers threatened to filibuster the process. That fierce opposition was highly unusual, especially given Hagel's credentials as a former senator. Plus, the Senate hadn't blocked a defense secretary nominee in a quarter-century.

So why is Perez, like Hagel before him, eliciting such a strong negative reaction?

For one thing, Perez heads the Justice Department's Civil Rights division. That branch has come under fire for a host of reasons, including allegations of harassment and mistreatment of employees due to their political leanings. In a report released Tuesday, department watchdogs concluded the division has been marred by "deep ideological polarization" and a "disappointing lack of professionalism."

The report did not cite Perez for any specific wrongdoing. And Perez was only appointed to the Justice Department in 2009, while the allegations cover the past 12 years, with the most serious infractions occurring during the Bush presidency. Still, Perez has acknowledged that he could do more to foster a better work environment now that the division is in his hands.

That admission of culpability was enough for some to question his credentials, including Washington Post columnist Jennifer Rubin.

"Does the leader of a critical division of the Justice Department that had to be warned to respect these basic principles of fairness and good governance warrant promotion to secretary of labor?" she wrote. "I don’t think so, but since we have Hagel there are apparently no standards for confirmation."

The National Review has echoed that sentiment in numerous articles posted online in the last 24 hours alone.

"If you thought Chuck Hagel’s confirmation battle was rough, just wait for the blood on the floor if Thomas Perez is appointed to be secretary of labor," John Fund wrote, continuing that the IG report was damning evidence that Perez was unfit for the job.

In addition, critics contend that even if you believe that the division-wide problems can't be pinned on Perez, the guy is still terrible at his job because he's lost a number of cases for the government. Rubin calls him a "cruddy lawyer," while Quin Hillyer of the American Spectator blasted him as "one of the most loathsome figures in the thoroughly loathsome political ranks of Obama's Justice Department" — a man who "doesn’t even seem to be a very good lawyer at all."

Others have been critical not only of Perez's work, but his character, too. They argue that Perez is a partisan hack whose efforts at the DOJ reveal a radical agenda and a racial bias against whites.

Naturally, Perez's job description requires him to oversee cases involving race, most notable among them the department's opposition to voter ID laws — which progressives view as little more than modern Jim Crow laws — on behalf of the White House. On Perez's watch, the division has also sued Arizona's hardline anti-immigration Sheriff Joe Arpaio, and pursued banks for discriminating against minority homeowners, just two of many efforts that pleased liberals and rankled conservatives.

For those efforts, Hillyer calls Perez,"radical, race-baiting," and said he has "led the administration’s racial scaremongering against voter ID laws." Michelle Malkin similarly warned that Perez has had an "extremist left-wing 'social justice' career." But she went further into Perez's past to justify that argument, pointing to Perez's volunteer work with Casa de Maryland, an immigration amnesty group that received funding from two familiar conservative bogeymen: billionaire George Soros, and deceased Venezuelan President Hugo Chavez.

Perhaps the most simple explanation for the fervent backlash is that Perez is loved by progressives. Given that a Republican nominee like Chuck Hagel faced a mountain of criticism and a filibuster threat, it's hardly surprising that a liberal nominee would face at least equally tough scrutiny.

Republicans already tried to block Perez's nomination to the DOJ in 2009, in part because of (since-disproven) accusations that the department dropped a case against the New Black Panther Party for political reasons. (That case arose and was settled long before Perez was even in the division.)

Still, Republicans have found enough else to criticize about Perez's past that they're already sounding the alarm. If Obama does in fact nominate him, the drum beat of opposition will only grow louder.