A federal prosecutor will testify to Congress on Wednesday that the Justice Department exerted "heavy pressure" on prosecutors in Roger Stone's criminal trial to request a more lenient sentence for Stone.Aaron Zelinsky, an assistant U.S. attorney in Maryland who was formerly assigned to Special Counsel Robert Mueller's Russia investigation, will testify to the House Judiciary Committee that prosecutors in Stone's criminal trial were under “heavy pressure from the highest levels of the Department of Justice to cut Stone a break.”Stone's sentencing was handled in an "unusual and unprecedented way" that Zelinsky found "deeply unsettling," he will testify, according to his prepared remarks.Stone was convicted of lying to Congress, witness tampering and obstructing the House’s investigation into the Trump campaign’s connections to Russia.Trump complained in February that the prosecutors' seven-to-nine-year sentencing recommendation constituted a “horrible and very unfair situation.” Shortly afterwards, his Justice Department submitted a revised filing stating that the prosecutors’ recommended lengthy sentence “could be considered excessive and unwarranted.” Zelinsky was one of four prosecutors to recommend Stone’s seven-to-nine year sentence who either resigned or quit the case after the DOJ weighed in.The White House has denied Trump pressured the DOJ to show lenience to Stone.Zelinsky's supervisors in the U.S. Attorney’s Office informed him that Stone, a longtime associate of President Trump's, was being treated differently because of his relationship to the president. The federal prosecutor said he was told that the acting U.S. Attorney for the District of Columbia, Timothy Shea, was under "heavy pressure from the highest levels of the Department of Justice to cut Stone a break, and that the U.S. Attorney’s sentencing instructions to us were based on political considerations.""I was also told that the acting U.S. Attorney was giving Stone such unprecedentedly favorable treatment because he was 'afraid of the President,'" Zelinsky will testify.Meanwhile, Zelinsky says he saw the DOJ exerting "significant pressure" on prosecutors to obscure the correct Sentencing Guidelines calculation for Stone as well as "water down and in some cases outright distort the events that transpired in his trial and the criminal conduct that gave rise to his conviction.""Such pressure resulted in the virtually unprecedented decision to override the original sentencing recommendation in his case and to file a new sentencing memorandum that included statements and assertions at odds with the record and contrary to Department of Justice policy," Zelinsky's remarks to Congress read.Zelinsky said he and other Assistant United States Attorneys "immediately and repeatedly raised concerns, in writing and orally" but their "objections were not heeded."Another Justice Department official, antitrust prosecutor John Elias, will also testify on Wednesday about a separate alleged instance of political bias within the DOJ. Elias will tell lawmakers that Attorney General William Barr ordered the department's Antitrust Division to probe ten marijuana company mergers because he “did not like the nature of their underlying business.”Both officials are testifying under subpoena.