Once the face of refereeing in the UFC, "Big" John McCarthy had a severe falling out with the promotion in 2008 when he took a job with Affliction MMA. McCarthy put himself in a position where he was on bad terms with the UFC as well as with many state athletic commissions due to obvious conflicts of interest and public statements that resided a bit outside the impartiality that is supposed to be the hallmark of a judge or referee.
He has, in recent years, began to show up in the Octagon once again and Dana White has praised some of the work he has done. That trend continued after this weekend's UFC on Fox 9 when Dana White was very positive about McCarthy's work during the event (via MMA Junkie):
"John McCarthy and I might have had our moments throughout the years, but I’ll tell you what I love about McCarthy, and it happened again tonight," he said following the event. "When John is in that octagon, he is in absolute and total control."
"Lauzon headbutted (his opponent Mac Danzig), and he stopped the fight and said, ‘Watch your head,’" he said. "Everybody in the arena knew there was a headbutt, and everybody watching on TV knew it was stopped and there was a warning for a headbutt. That’s what you do.
"Are [McCarthy and Dean] perfect? Are they going to make mistakes? Sometimes they are," White said. "But it’s hard to argue that they’re the best in there."
Given some of the issues the UFC has seen in recent years with referees, it's not exactly surprising to see a 180 on McCarthy's place reffing fights for the promotion.