US Attorney General William Barr has put himself on a possible collision course with Donald Trump by saying the president's tweets about legal matters make it impossible for him to perform his duties.
Mr Barr's comments added an incendiary twist on a day in which House Democrats attacked him for politicising law enforcement.
Rather than hit back, Mr Barr deflected the criticism as he rounded on Mr Trump.
In an interview with ABC News, Mr Barr said the president's tweets about Justice Department prosecutors and various cases "make it impossible for me to do my job".
The comments came in a week in which Mr Trump fired two men who testified against him in his impeachment trial - European Union ambassador Gordon Sondland and National Security Council staffer Lieutenant Colonel Alexander Vindman.
House Democrats, frustrated over the Senate's acquittal of Mr Trump in his impeachment trial, turned their attention to Mr Barr's department and what they called his efforts to politicise federal law enforcement.
Democrats have demanded more information about Mr Barr's intervention in the case of Roger Stone, a long-time confidant of President Donald Trump who was convicted in November.
Mr Barr this week overruled prosecutors who had recommended Stone be sentenced to seven to nine years in prison.
House Speaker Nancy Pelosi described Mr Barr as one of the president's "henchmen".
"The attorney general has stooped to such levels," Ms Pelosi said. "What a sad disappointment. The American people deserve better."
Mr Barr also said on ABC, however, that his decision to undo the sentencing recommendation was made before Mr Trump tweeted about it.
Despite his criticism of the president, he also said Mr Trump had not asked him to intervene in any cases.
Mr Trump tweeted about the Stone case on Thursday, saying the jury foreperson in his case had "significant bias", and the case overall was "not looking good for the 'Justice' Department".
The sharpened look at Mr Barr's activities comes at a time when many Democrats appear wary of prolonging the Ukraine inquiry that led to Mr Trump's impeachment.
Ms Pelosi and House Intelligence Committee Chairman Adam Schiff have so far put off - but not ruled out - a subpoena for former national security adviser John Bolton, who refused to participate in the House impeachment inquiry but later said he would testify in the Senate trial. Mr Bolton is writing a book.
Issuing a subpoena for Mr Bolton could bring dramatic testimony about Mr Trump's conduct, but could also risk a court fight that may take months to resolve.
Many Democrats privately say they want to look forward and conduct oversight of Mr Trump's actions in real time. First up will be examining Mr Barr's intervention in the Stone case.
Mr Stone was convicted of lying to Congress, witness tampering and obstructing the House investigation into whether the Trump campaign co-ordinated with Russia to tip the 2016 election result.
Mr Trump congratulated the attorney general afterwards on Twitter. Meanwhile, the four prosecutors on the case immediately withdrew.
The turmoil within the Justice Department has given Democrats a new way forward for their investigations.
While there is little interest in pursuing another impeachment, House Democrats want to leverage the power of their majority to conduct oversight as they try to defeat Mr Trump in the November election.
"The resignation and defection of these prosecutors is a huge alarm bell going off in our system," said Representative Jamie Raskin of Maryland, one of the most vocal on the House Judiciary Committee who pushed for impeachment.
House Judiciary Committee Chairman Jerrold Nadler has announced Mr Barr would testify before the committee on March 31 and representatives would ask about his involvement in the Stone case.
People familiar with the committee's plans, who requested anonymity, said there could be other judiciary committee hearings before then to examine the politicisation of the department.
Democrats also want to ask Mr Barr about his decision to take information from Mr Trump's personal lawyer, Rudy Giuliani, about Democratic presidential candidate Joe Biden and his son. Those same efforts by Mr Giuliani in Ukraine were at the heart of Mr Trump's impeachment.
"In the past week alone, you have taken steps that raise grave questions about your leadership," the Democrats wrote in a letter to Mr Barr.