During his term, he received criticism from many for his handling of several challenges, including his letter on the Mueller report, interventions in the convictions and sentences of former advisors to President Trump, Roger Stone and Michael Flynn,[5][6] his order of the federal government to resume federal executions after 17 years,[7][8] and allegations of political interference in the removal of Geoffrey Berman from his Southern District of New York attorney position in a matter pertaining to the indictment of Turkish bank Halkbank, a bank with close personal ties to Recep Tayyip Erdoğan.

[53] In October 1992, Barr appointed then retired New Jersey federal judge Frederick B. Lacey to investigate the Department of Justice and the Central Intelligence Agency handling of the Banca Nazionale del Lavoro (BNL) Iraqgate scandal.

House Banking Committee Chairman Henry B. González called for Barr's resignation, citing "repeated, clear failures and obstruction" by the Department of Justice in allegedly delaying an investigation of the BNL-Iraqgate case.

After becoming impatient with the slow pace and inaction of the Justice Department under Barr, Kerry had the investigation turned over to New York State District Attorney Robert Morgenthau, who managed to extract a plea agreement with BCCI for various criminal violations and the indictment of First American Chairman Clark Clifford.

[59] The DoJ inspector general concluded that this program had been launched without a review of its legality and made 16 recommendations including areas relating to subpoena procedures and guidance training materials.

[2] Upon leaving the DOJ in 1993, Barr was appointed by Virginia Governor George Allen to co-chair a commission to implement tougher criminal justice policies and abolish parole in the state.

In 2017, he faulted Mueller for hiring prosecutors who have contributed to Democratic politicians, saying that his team should have had more "balance", and characterized the obstruction of justice investigation as "asinine" and that it was "taking on the look of an entirely political operation to overthrow the president".

[115] Also in July 2019, Barr reportedly made the decision to not bring federal civil rights charges against New York policeman Daniel Pantaleo for causing the death of Eric Garner.

Since 2014, Firtash had been fighting extradition to the United States under a federal indictment while he was living in Austria after being arrested there and released on $155 million bail, and diGenova and Toensing sought to have Barr drop the charges.

Prior to meeting with diGenova and Toensing, Barr had been briefed in detail on the initial Trump–Ukraine scandal whistleblower complaint within the CIA that had been forwarded to the Justice Department, as well as on Giuliani's activities in Ukraine.

Bloomberg News reported that its sources told them Giuliani's high-profile publicity of the Shokin statement had greatly reduced the chances of the Justice Department dropping the charges against Firtash, as it would appear to be a political quid pro quo.

[16] In February 2020, Senator Lindsey Graham stated that the Justice Department "is receiving information coming out of the Ukraine from" Rudy Giuliani, a personal lawyer to president Donald Trump.

In it, Mueller complained that the summary "did not fully capture the context, nature, and substance" of the Special Counsel's probe, adding, "There is now public confusion about critical aspects of the results of our investigation.

[179] On May 8, 2019, the House Judiciary Committee voted along party lines to hold Barr in contempt of congress for failing to comply with a subpoena which requested the full and unredacted Mueller Report.

"[182][183] In March 2020, Reggie Walton, a federal district judge originally appointed by President George W. Bush, criticized Barr's characterizations of the Mueller report as "distorted" and "misleading".

The reason for the refusal was that the committee's decision to not allow a Justice Department lawyer to accompany Gore during testimony violated "the confidentiality interests of the Executive Branch" (though a separate room was permitted).

[201] In July 2019, the House of Representatives voted 230–198 to hold Barr (and Commerce Secretary Wilbur Ross) in criminal contempt of Congress, after they failed to produce documents as April 2019 congressional subpoenas mandated.

[253] Additionally in February 2020, Barr declared that there would be a review of the criminal case of Michael Flynn, the former National Security Advisor to Trump, who had pled guilty in 2017 to lying to the FBI about his contacts with a Russian ambassador.

[277] On August 4, 2020, Barr and presidential adviser Ivanka Trump, and special advisor Heather Fischer announced the $35 million in grant awards to support victims of human trafficking at a White House event.

Barr equated the movement with antifa, characterizing that loose collective as "highly organized" and claiming "the media doesn't take footage of what's happening" at George Floyd protests.

[285][286] In an August 2020 interview, Trump claimed that a plane full of "thugs in dark uniforms", implying antifa, had recently flown from one unidentified city to another with the intention of fomenting riots.

[301] The day after Barr's interview, the Department of Homeland Security issued an intelligence bulletin warning that Russia is using social media and other venues to promote false claims that mail voting will lead to widespread fraud, in order "to undermine public trust in the electoral process".

[320] Trump was also angered by news that Barr had followed Justice Department policy by not disclosing during the campaign that Joe Biden's son Hunter had since 2018 been under criminal investigation, initially on suspicion of money laundering but later for tax matters.

The Washington Post noted that the Justice Department traditionally seeks to avoid impugning individuals who are not charged with crimes, and the DOJ is not involved in exposing political "dirty tricks" that have not been found unlawful.

Webster asserted that "the integrity of the institutions that protect our civil order are, tragically, under assault," writing that "aspersions cast upon [FBI employees] by the president and my longtime friend, Attorney General William P. Barr, are troubling in the extreme.

They wrote that Barr's actions as attorney general "have undermined the rule of law, breached constitutional norms, and damaged the integrity and traditional independence of his office and of the Department of Justice".

In a 1991 op-ed in The New York Times, Barr argued that death row inmates' ability to challenge their sentences should be limited to avoid cases dragging on for years: "This lack of finality devastates the criminal justice system.

[358] Barr donated $55,000 to a political action committee that backed Jeb Bush during the 2016 Republican Party presidential primaries and $2,700 to Donald Trump during the general election campaign.

[367] In July 2020, Barr condemned large American tech companies, such as Google, Microsoft, Yahoo, and Apple,[368] and Hollywood studios, accusing them of "kowtowing" to the Chinese Communist Party for the sake of profits.

[43] During a US Attorneys’ National Conference on June 26, 2019, Barr surprised attendees by standing up in the middle of an NYPD Emerald Society performance, and joined them in playing Scotland the Brave with a bagpipe.