In the late 1990s, when the Clinton White House was under siege amid revelations of the president’s affair with Monica Lewinsky and efforts by Congress to impeach him, it fell on Joe Lockhart, then the White House spokesman, day after day to defend his boss.

But unlike many of his predecessors, he did not just take his marching orders. In countless meetings with the president and his advisers, Lockhart helped shape the message he would convey, and he aggressively pressed it to reporters.

“He was out there, he was on point, he was wearing his cleats,” said Doug Sosnik, an adviser to the president who worked closely with Lockhart at the time. “He’s a tough guy, willing to say what needs to be said, and he’s not worried about what people are saying about him.”

People have a lot to say about him again.

Last year, Lockhart took his pugnacious style to another embattled institution, the National Football League, where the lifelong Democratic operative has found himself in the conservative confines of a league staggered by the reaction to players’ demonstrating during the playing of the national anthem at games, as well as cases involving domestic violence, concussions, player misconduct and an array of other issues.