Historian Steve Kantrowitz, who graduated from Yale with a B.A. in history in 1987, is calling into question Supreme Court nominee Brett Kavanaugh’s claim to have been a virgin throughout college.

Kantrowitz, who is now a history professor at the University of Wisconsin-Madison, writes on Twitter that he can recall Kavanaugh discussing his sexual exploits during their freshman year at Yale.

“Perhaps Brett Kavanaugh was a virgin for many years after high school,” Kantrowitz writes. “But he claimed otherwise in a conversation with me during our freshman year in Lawrance Hall at Yale, in the living room of my suite.”

Perhaps Brett Kavanaugh was a virgin for many years after high school. But he claimed otherwise in a conversation with me during our freshman year in Lawrance Hall at Yale, in the living room of my suite.

— Steve Kantrowitz (@skantrow) September 25, 2018

In his past tweets, Kantrowitz has expressed liberal views and has spoken out against Kavanaugh’s confirmation on political grounds. The latest tweet, however, marks the first time that the professor has called out the Supreme Court nominee for being dishonest while talking about his personal life.

Kantrowitz’s tweet was cited by New Yorker reporter Jane Mayer, who said that such claims cut to the heart of Kavanaugh’s credibility as an honest person.

Another Yale Classmate Rebuts Kavanaugh: was he lying then, or last night on Fox? This classmate is now an award-winning history professor. https://t.co/bj9uooB4QQ

— Jane Mayer (@JaneMayerNYer) September 25, 2018