During my final semester as a collegian, we revised our Code of Standards to say that no smoking is allowed with our letters showing. It was a chapter rule, which didn't really matter anyway because only three of us smoked. Even then, I remember wearing my letters and just feeeeeeeening for a cigarette.
The no drinking in letters thing was always a rule.
As for drinking with lavalieres on, personally I'm pretty lenient with it. Sometimes, say at Taco Tuesday, you forget that you have it on. Technically you're still wearing your letters, but as long as your lavaliere isn't 10 inches tall then it's okay by me.
The Code of Standards only applied to collegians, but even as alums we still hold ourselves to it because we like setting good examples for our youngins.
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