The tuxedo (or smoking jacket) traditionally it is not ceremony wear but more party wear.
So, even though it wouldn't really be appropriate for a wedding, exceptions can be made for late ceremonies, and really elegant and sophisticated parties.
COLOUR: black - no to white tuxedos, please!
WHO: every guest has to wear it
ACCESSORIES: bow tie or slim black tie
NOT TO: To be avoided for morning ceremonies and very formal church functions.