Republicans lawmakers made an explosive allegation on Tuesday, accusing House Intelligence Committee Chairman Adam Schiff (D-CA) of stopping an impeachment witness from answering Republican members’ questions.

“He’s directing witnesses not to answer questions that he doesn’t want the witness to answer if they’re asked by Republicans,” House Minority Whip Steve Scalise (R-LA) charged. “He’s not cut off one Democrat. He’s not interrupted one Democrat and told a witness not to answer Democrat members’ questions but today he started telling witnesses not to answer questions by certain Republicans.” He added, “that reeks.”

Scalise said Schiff’s handling of the ongoing impeachment inquiry “reeks” and compared it to a “one-sided, Soviet style process.”

“Speaker Pelosi’s resolution confirms that it is an impeachment inquiry, yet every other impeachment inquiry we’ve had in the history of our country—all three—have allowed both sides to call witnesses, have allowed the White house to participate. That’s not happening,” Scalise complained. “That might be what they did in the Soviet Union—not the United States of America.”

Starting today, according to Scalise and Rep. Jim Jordan (R-OH), Schiff started barring Republicans from asking certain questions.

They said when Jordan tried to ask “star witness” Lt. Col. Alexander Vindman some basic questions about the July phone call, Schiff told Vindman he didn’t have to answer them.

Jordan said he tried to ask Vindman who he talked to after the call, but “Adam Schiff says, ‘no-no-no we’re not going to let him answer that question!’”

Vindman, who serves as a director on the National Security Council (NSC), appeared before the House Permanent Select Committee on Intelligence, the House Committee on Foreign Affairs, and the House Committee on Oversight and Reform, for a closed door deposition.

He testified that he’d had concerns about the July phone call between President Trump and Ukrainian President Volodymyr Zelensky and reported his concerns to the NSC’s lead counsel.

Democrats opened their impeachment inquisition against the president last month after an anti-Trump “whistleblower” alleged that Trump pushed Zelensky to investigate former Vice President Joe Biden and his son Hunter in exchange for military aid.

“The Democrats run out here and say, ‘ooh, the Republicans are trying to figure out who the whistleblower is,'” Jordan continued. “We’re trying to figure out who our witness list is! The resolution that the Speaker has just filed … she points this out in the resolution that this is going to go to the Judiciary Committee if in fact they push it there. There will be witnesses called. We would like to figure out who those witnesses should be.”

“Our witness today is under subpoena,” Jordan said. “He’s supposed to answer the questions from members of the United States Congress—not just from members of the majority of the United States Congress. When it’s a subpoena from congress we all get to ask questions and Adam Schiff doesn’t get to say ‘you can answer our questions, witness, but you can’t answer the Republicans’ questions.”

Fed up with what he called a “tainted process,” Scalise told reporters, “it’s clear Pelosi needs to declare a mistrial.” He added, “what happened today confirms even worse just how poorly Adam Schiff is handling this process in denying the ability for Republicans to even ask basic questions that are critical to the heart of whether or not a president of the United States is impeached.”