House Republicans have been trying to throw sand in the gears of the impeachment inquiry from the start. Nadler, along with Intelligence Committee Chairman Adam Schiff before him, has largely succeeded in keeping things on track. But the frequency and fervor with which the GOP lawmakers objected today seemed to trip Nadler up a bit, and they focused relentlessly on the Democrats’ unusual if not unprecedented structure for the hearing.

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Republicans had hoped that Schiff would testify about his committee’s report, which would give them an opportunity to question the chairman on whether he ever met the anonymous whistle-blower whose August complaint to Congress set off the investigation. (Schiff has denied any such meeting.) There is precedent for both congressional staff and elected members testifying before congressional committees, but Democrats decided to shield Schiff by inviting only committee staff members to appear. Republicans responded by displaying a poster with Schiff’s image on a milk carton.

The setup got odder from there. Officially, the Judiciary Committee was to hear presentations from both the Intelligence Committee’s counsel and its own staff counsel—the veteran lawyers who have become familiar to close observers of the impeachment hearings over the past few weeks. Because Castor has been filling both roles for Republicans, only he appeared on the GOP side. The Democrats had Berke, from the Judiciary Committee, and Goldman, from the Intelligence Committee.

Berke opened with a flourish, presenting the case for impeachment without notes or a prepared text, as if he were delivering a closing statement before a courtroom in a jury. But after giving his testimony from the witness stand, he returned to the committee dais to ask questions of Goldman and himself.

Republicans were astounded.

“He can either ask or answer. He can’t do both,” protested Representative Doug Collins of Georgia, the committee’s top Republican.

“It’s just wrong!” bellowed Representative Louie Gohmert of Texas.

Nadler confused matters further by telling Republicans that Berke was appearing on behalf of the Judiciary Committee, not as a witness, although he had referred to him as a witness earlier. Republicans were also peeved that unlike Goldman and Castor, Berke was not sworn to testify under oath.

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Today’s sessions did allow both parties to cross-examine the men who have, in effect, played the roles of prosecutor and defense attorney for the past several weeks. Castor appeared uncomfortable in the witness chair as Berke tried to poke holes in his defense of the president. Asked about the central charge in the impeachment case—that in the infamous July phone call, Trump asked Ukrainian President Volodymyr Zelensky for the favor of helping to investigate his political rival, former Vice President Joe Biden—Castor replied: “I think it’s ambiguous.” At various points, Republicans tried to step in to protect Castor. “The lawyer is badgering the witness,” Representative James Sensenbrenner of Wisconsin said of Berke. Nadler defended his counsel, saying it was simply “sharp cross-examination.”