Defending a friend who’s wrong isn’t loyalty. Telling them they’re wrong is.

Loyalty gets confused with agreement, and the two pull opposite ways when somebody you care about is in the wrong. Backing a bad position in public leaves your friend no route to correct it, and keeps them somewhere they will eventually have to climb out of alone. Whoever is willing to say it privately is the one actually on their side.

Take it to them first, quietly, in a sentence about what happened rather than about who they are. You can still refuse to pile on in front of other people. Being the friend who tells the truth is worth the awkward evening.