This response is provided based on the information you shared and should not be used as the sole source for making a decision. You should seek guidance from the chain of command, IG, JAG or other certified agencies before making any decisions. How you chose to use this information is totally up to you and is your sole responsibility.
There is not regulation that governs this subject. The only time I can imagine a leader giving this type of order is if the drinking in some way endangered the Soldier or caused a safety risk. Short of that I see no value in such an order.
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