i see the point of not punishing the whole chapter, but i also see the other side too. i'm a former chapter advisor and now a greek advisor. the chapter advisor in me says "why didn't someone see their sorry drunk ass and send them home in a cab?" someone should have done something about it. what about those that did nothing....shouldn't something be done to them so that they know next time to send those drunks home? i would address those that were drunk and those that did nothing, but from the chapter's descipline process.
as for the greek advisor in me, i would make sure those drunks are getting punished by the chapter and make sure it follows through with the punishment. i would also want to make sure the chapter knows the alcohol policies of the chapter and the school. this would probably be in the form of a mandatory presentation or perhaps a police ride along or both.
if i know the chapter is taking care of it's own problems, i am less likely to impose something on them. if they are not taking care of it, i will step in more.