On Tuesday, it was reported that special counsel Robert Mueller wrote a letter challenging Attorney General William Barr over his four-page summary of the Russia investigation, claiming he mischaracterized their findings. Democrats believe Barr’s summary was an intentional attempt to protect President Donald Trump from the report’s damaging findings, and many of them are speaking out against Barr.

Upon Tuesday’s revelation, 2020 Democratic nominee Julián Castro has called on Barr to resign, accusing him of “willfully” misleading the nation “to cover up attempted crimes by Donald Trump.”

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Additionally, Rep. Jerrold Nadler (D-N.Y.), the chairman of the House Judiciary Committee, is calling for the release of Mueller’s letter. Nadler adds how Barr “must answer for this” and that Mueller “must be allowed to testify.”

Senate Minority Leader Chuck Schumer (D-NY) tweeted out how the “misleading nature” of Barr’s testimony and press conferences last month is now “even more glaring,” concluding that “it’s time for Mueller to testify publicly.”