WASHINGTON (AP) — House Democrats frustrated over the Senate’s acquittal of President Donald Trump are pushing their oversight efforts toward the Justice Department and what they call Attorney General William Barr’s efforts to politicize federal law enforcement.

Democrats have demanded more information about Barr’s intervention in the case of Roger Stone, a longtime confidant of President Donald Trump who was convicted in November. Barr this week overruled prosecutors who had recommended that Stone be sentenced to 7 to 9 years in prison.

House Speaker Nancy Pelosi criticized Barr on Thursday, calling him one of Trump’s “henchmen.”

“The attorney general has stooped to such levels,” Pelosi said. “What a sad disappointment. The American people deserve better.”

The sharpened look at Barr’s activities comes at a time when many Democrats appear wary of prolonging the Ukraine inquiry that led to Trump’s impeachment. 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. Bolton is writing a book.

Issuing a subpoena for Bolton could bring dramatic testimony about Trump’s conduct, but also risk a court fight that could take months to resolve. Many Democrats privately say they want to look forward, not backward, and conduct oversight of Trump’s actions in real time.

First up will be examining whether Barr inappropriately intervened in the Stone case. Stone was convicted of lying to Congress, witness tampering and obstructing the House investigation into whether the Trump campaign coordinated with Russia to tip the 2016 election.

Trump congratulated the attorney general afterward 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 after the sting of the Senate’s impeachment acquittal. While there is little interest in pursuing another impeachment case, Democrats want to leverage the power of their majority to conduct oversight as they try to defeat Trump at the polls in November.