Senate Minority Leader Charles SchumerChuck SchumerBiden 'encouraged' by meeting with congressional leaders on infrastructure Republicans welcome the chance to work with Democrats on a bipartisan infrastructure bill Cheney sideshow distracts from important battle over Democrats' partisan voting bill MORE (D-N.Y.) is demanding that Attorney General William BarrBill BarrSenate Democrats urge Garland not to fight court order to release Trump obstruction memo Lawyer for former officer charged in George Floyd death alleges witness coercion CNN legal analyst joins DOJ's national security division MORE bring a letter from special counsel Robert MuellerRobert (Bob) MuellerSenate Democrats urge Garland not to fight court order to release Trump obstruction memo Why a special counsel is guaranteed if Biden chooses Yates, Cuomo or Jones as AG Barr taps attorney investigating Russia probe origins as special counsel MORE raising concerns about his four-page March memo to a Senate hearing on Wednesday. 
"In light of Mueller's letter, the misleading nature of Barr’s 4/10 testimony & 4/18 press conference is even more glaring. Barr must bring the letter with him when he testifies in the Senate tomorrow," Schumer said in a tweet on Tuesday night. 
He added that "it's time for Mueller to testify publicly. Now." 
Schumer's tweet comes after The Washington Post reported that the special counsel wrote in a letter that Barr’s March 24 memo did not "capture the context, nature, and substance" of his findings on Russia's election interference and the Trump campaign. 
"There is now public confusion about critical aspects of the results of our investigation. This threatens to undermine a central purpose for which the Department appointed the Special Counsel: to assure full public confidence in the outcome of the investigations," Mueller wrote in the letter, according to the Post. 
Justice Department spokeswoman Kerri Kupec said in a statement to The Hill that Mueller “expressed frustration over the lack of context and the resulting media coverage” of his obstruction inquiry in a phone call following the release of Barr’s memo. 
Kupec added that Barr’s phone call with Mueller was “cordial and professional” and said Mueller emphasized that “nothing in the Attorney General’s March 24 letter was inaccurate or misleading.”
But Democrats have seized on reports of the letter from Mueller to reignite their questions over Barr's handling of the report on the two-year investigation into Russia's election meddling in the 2016 election.
Barr is scheduled to testify on Wednesday before the Senate Judiciary Committee, where he will likely face a grilling over the letter, which was released less than a day before his hearing. 
Sen. Richard Blumenthal (D-Conn.), a member of the panel, told CNN on Tuesday that he believed Barr, whom he voted against, remained unfit for his position. 
"I believe he is unfit, even more so today. ... What the remedy should be, I'm going to be talking to my colleagues," he said. 
Sen. Christopher CoonsChris Andrew CoonsBiden to go one-on-one with Manchin US, Iran signal possible breakthroughs in nuke talks How the United States can pass Civics 101 MORE (D-Del.), another member of the committee, added that that "Barr owes the American people an explanation. Tomorrow’s public hearing in front of the Senate Judiciary Committee is a good place to start." 
"For anyone out there who still doubted it, Mueller’s letter shows that Attorney General Barr has always been the chief propagandist for President TrumpDonald TrumpSunday shows preview: House GOP removes Cheney from leadership position; CDC issues new guidance for fully vaccinated Americans Navajo Nation president on Arizona's new voting restrictions: An 'assault' on our rights The Memo: Lawmakers on edge after Greene's spat with Ocasio-Cortez MORE. His four page letter totally misled Congress and the public. He should resign immediately," he said.