Charles Ellicott Commentary Esther 1:8

"And the drinking was according to the law; none could compel: for so the king had appointed to all the officers of his house, that they should do according to every man`s pleasure." — Esther 1:8 (ASV)

Law. —Rather ordinance or decree, that is, specially issued for this occasion. What this means is shown by what follows, namely, that the king had issued special orders to allow all to do as they pleased in the matter of drinking, instead of as usual compelling them to drink. This degrading habit is the more noticeable because the Persians were at first a nation of exceptionally temperate habits.