"I reported the Bloomberg article to Facebook as 'False News.'"

Writes John at Facebook, linking to a Bloomberg article with the headline, "Kavanaugh Wrongly Claims He Could Legally Drink in Maryland."

From the hearing transcript:

My friends and I sometimes got together and had parties on weekends. The drinking age was 18 in Maryland for most of my time in high school, and was 18 in D.C. for all of my time in high school. I drank beer with my friends. Almost everyone did. Sometimes I had too many beers. Sometimes others did. I liked beer. I still like beer..

That does suggest he drank beer when he was underage, but I don't see him claiming that it was legal.