I know several people (yes, more than one) who have been convicted of DUI for riding their horse while under the influence of alcohol.
Sooo...following that reasoning, if you are sober, but carry a drunk friend home on your back, can that friend be convicted of DUI even though you're sober?
Ah...The drunk might be in compliance, but the person carrying the drunk must have proper, approved training for carrying drunks, and must be certified.