Washington (CNN) A constitutional law expert fiercely defended her knowledge of the impeachment inquiry Wednesday before the House Judiciary Committee after the panel's top Republican suggested she wasn't read up on the proceedings.

Pamela Karlan, a professor at Stanford University, was responding to Rep. Doug Collins, who said the four professors invited to speak about impeachment were "in here today to testify on stuff most of you have already written about."

"Unless you're really good on TV or (have been) watching the hearings for the last couple weeks, you couldn't have possibly actually digested the Adam Schiff report from yesterday or the Republican response in any real way," Collins said, referring to the report released Tuesday by the House Intelligence Committee that claimed evidence of President Donald Trump's alleged misconduct and obstruction of Congress is "overwhelming."

"Mr. Collins, I would like to say to you, sir, that I read transcripts of every one of the witnesses who appeared in the live hearing because I would not speak about these things without reviewing the facts," Karlan said during the panel's first hearing in House Democrats' impeachment inquiry into Trump.

The Trump-Ukraine impeachment inquiry report, annotated House Intelligence Committee Democrats released a 300-page report outlining their months-long impeachment inquiry into the conduct of President Donald Trump.

"I'm insulted by the suggestion that as a law professor I don't care about those facts," she said, visibly frustrated by the Georgia Republican's remarks.

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