Formal debate, could we make it a semi formal debate? A gentleman wears a white bow tie with his tuxedo to anything formal but is allowed to wear a black bow tie to a semi formal event/meal if the event/meal starts before 7 PM and I have some how misplaced my white tie. If you would make it an informal debate then I can wear a white informal dress shirt, with buttons instead of studs, under my tuxedo jacket, but a black bow tie is still required. We could do informal before 7 PM in which case a gentleman may wear a conservative black suit and four-in-hand tie, sorry no sport jackets allowed. Ladies can also wear knee length tea dresses instead of ankle length fromal dresses to any informal event.