יט אִם–עַל–הַמֶּלֶךְ טוֹב יֵצֵא דְבַר–מַלְכוּת מִלְּפָנָיו וְיִכָּתֵב בְּדָתֵי פָרַס–וּמָדַי וְלֹא יַעֲבוֹר אֲשֶׁר לֹא–תָבוֹא וַשְׁתִּי לִפְנֵי הַמֶּלֶךְ אֲחַשְׁוֵרוֹשׁ וּמַלְכוּתָהּ יִתֵּן הַמֶּלֶךְ לִרְעוּתָהּ הַטּוֹבָה מִמֶּנָּה
“If it is good for the king, let the word of the kingdom go out from you and let it be written in the rules of Persia and Medea – and let it not be transgressed – that Vashti will not come before the King Achashverosh, and the king should give her royalty to [one who] appears better than her.”
In Ohr Chadash, the Maharal writes that Memuchan is suggesting Achashverosh have the story written, not the law. After all, what law is he establishing; that Vashti can no longer appear before him? By publishing the incident itself, Achashverosh will be remembered positively in history (according to Memuchan) by establishing this precedent case.