"Everything about it was foolish," Mercutio replies, hopping unsteadily up on the nearest table to lounge on it, kicking his heels. "I am glad I was avenged, of course, but little good it does me here; and ay, Romeo got justice, for whatever comfort it gave him." He shifts a bit, suddenly feeling like a bug pinned down for inspection.

"...Ay. You've the right of it," he says after a moment, carefully looking anywhere but at Claudius. It's useless to lie about it here, he knows well enough that Claudius will uncover it sooner or later. And why should it even matter? Tybalt may never arrive, or Romeo, for that matter. There is no one to disapprove here.