I have an awkward problem. One of my fiance's cousins has a boyfriend that frankly I don't want at the wedding. My fiance's brother got married a few months ago and the cousin attended with the (at the time) new boyfriend. It was a disaster. The cousin and boyfriend showed up high, loudly snickered the whole way through the ceremony, snuck outside to continue the high, and to top it off, the boyfriend poured a full beer on the floor right in front of the bride saying "oops guess you should clean that up." To the bride!! The couple was a highlight the whole night for all the wrong reasons.
I understand that etiquette would require me to invite this boyfriend but I know he's going to cause problems. We're having our ceremony and reception at a venue sharing property with a police training ground - I have nightmares of the boyfriend (and probably cousin) getting arrested for either public intoxication or possession.
What can I do? I have a day-of coordinator that I can ask to keep an eye on the couple, but is there a way nip the problem in the bud?