My significant other is an economics professor in London and sits on students' PhD committees (he's second from bottom). At this PhD defense, the student wore a tux & tails, committee members wore robes & cravats. I would've died if this had been my defense.
P.S. All that's missing? Powdered wigs.
P.P.S. What's with the tuxedo dudes flanking the student?
P.P.P.S. Check out the wall-o-dead-guy-portraits. Very funny.