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The House Judiciary Committee today held its first hearing of the impeachment investigation, questioning constitutional scholars on whether the elements of President Trump’s pressure campaign on Ukraine amount to impeachable offenses. Here’s a recap.

Who testified?

The hearing, which spanned over eight hours, featured four law professors: Noah Feldman of Harvard, Pamela Karlan of Stanford, Michael Gerhardt of the University of North Carolina and Jonathan Turley of George Washington University.

Mr. Feldman, Ms. Karlan and Mr. Gerhardt were called in by Democrats, while Mr. Turley was requested by Republicans.

Why did they testify?

As a first step, Democrats on the House Judiciary Committee hoped for outside experts to establish — in public and on the record — the language and conceptual framework for what could soon be articles of impeachment.