WASHINGTON — When Democrats on the House Judiciary Committee present their opening arguments for impeaching President Trump on Monday, they will turn not to a seasoned prosecutor but to one of the nation’s leading defense lawyers to set the stage.

Barry H. Berke, a New York-based white-collar defense lawyer, has served as the special oversight counsel to the committee since February, working to build the investigative framework that now appears destined to end in the impeachment of Mr. Trump. On Monday, he will take a rare turn at the witness table to present for 30 minutes the facts before the committee and how they square with the law.

Mr. Berke will not be the only House lawyer publicly presenting on Monday. Daniel S. Goldman of the Intelligence Committee will orally present his panel’s two-month inquiry concluding that Mr. Trump abused his office to pressure Ukraine to investigate his political rivals. Stephen R. Castor will represent Republicans on both the judiciary and intelligence panels.

But Mr. Berke will be the first witness to speak, setting the tone for the proceeding and a week that could end with the Judiciary Committee voting to recommend impeachment articles.