CNN — Attorney General Merrick Garland forcefully rebuked congressional Republicans who have accused the Justice Department of political bias as he opened a contentious House Judiciary Committee hearing in Washington on Wednesday.

“I am not the president’s lawyer,” Garland said in his opening statement. “I will also add that I am not Congress’s prosecutor. The Justice Department works for the American people.”

He said that the Justice Department’s job is “to pursue justice, without fear or favor” and not to “do what is politically convenient” or “take orders from the President, from Congress, or from anyone else about who or what to criminally investigate.”

Republicans on the panel are expected to grill Garland with questions about the investigation into President Joe Biden’s son Hunter Biden and his now-scuttled plea deal, as well as special counsel Jack Smith’s two indictments of Trump.

“The fix is in. Even with the face-saving indictment last week of Hunter Biden, everyone knows the fix is in,” House Judiciary Chairman Jim Jordan said in his opening statement.

Against that backdrop, Garland told lawmakers that the department welcomes “public scrutiny, criticism, and legitimate oversight,” but “singling out individual career public servants who are just doing their jobs is dangerous – particularly at a time of increased threats to the safety of public servants and their families.”

“We will not be intimidated,” Garland said. “We will do our jobs free from outside interference. And we will not back down from defending our democracy.”

Preview of impeachment inquiry

Wednesday’s hearing is likely to offer a preview of the House Republican’s impeachment inquiry into the president – which will have its first hearing next week – and the partisan brawling that will accompany it.

The bulk of the allegations Speaker Kevin McCarthy said Republicans are investigating in the impeachment inquiry relate to Hunter Biden’s business dealings, though Republicans have uncovered no evidence to date that the president personally received any money. The House Judiciary Committee has also been probing allegations from an IRS whistleblower that the Justice Department investigation into Hunter Biden was politically tainted.

Despite the partisan rancor of the political probes and the looming impeachment inquiry, Garland is unlikely to say much about either the Hunter Biden or Trump investigations because they are ongoing.

Rep. Jerry Nadler of New York, the panel’s top Democrat, charged that Republicans had “poisoned” the committee’s oversight role.

“House Republicans will use their time today to talk about long-discredited conspiracy theories and Hunter Biden’s laptop. And they will do it because they care more about Donald Trump than they do about their own constituents,” Nadler said.

Investigation into plea deal

Jordan started an investigation into Hunter Biden’s now-scuttled plea deal in July, and he’s asked US Attorney-turned special counsel David Weiss, who negotiated the plea agreement with Hunter Biden, to testify before the committee in October.

Weiss’ June plea agreement with Hunter Biden on tax and gun charges – in which the president’s son agreed to plead guilty to federal tax charges and was likely to avoid jail time – fell apart in July amid scrutiny from a federal judge. Weiss subsequently requested special counsel status from Garland and indicted Hunter Biden on gun charges last week. Hunter Biden told the court Tuesday he will plead not guilty.

In addition, Jordan, a top Trump ally on Capitol Hill, has started an investigation into Smith’s twin probes of the former president. Jordan has also proposed budget cuts to the FBI and DOJ over the investigations.

Several House Republicans – including McCarthy – have floated an impeachment of the attorney general, although those calls have quieted down as House Republicans have turned their impeachment lens on President Joe Biden himself.

This story has been updated with additional developments.

CNN’s Annie Grayer contributed to this report.