What does Esther 1:15 mean?

He asked them, 'According to the law, what should be done to Queen Vashti? She didn't obey the command King Xerxes sent through the eunuchs.' Esther 1:15 - Modern Text Bible

(Xerxes wants to know the legal consequences for Vashti's refusal, treating it as a matter of law, not just personal offense.)