Purim Legalities
Question #1: Achashverosh complies with Esther's request to undo
his decree by issuing a new decree authorizing the Jews to defend
themselves. This is peculiar, as one would expect him to simply
nullify the old decree. A legislative body has the power to revoke
its own legislation.
Question #2: How is Achashveroshe's institution of a new tax
relevant to the story of the Megillah and therefore worthy of
recounting.
Question #3: Why did Achashverosh kill the sons of Haman? What did
they ever do to him?
Question #4: Once Achashverosh was killing off Haman's family, why
did he not kill Haman's wife Zeresh?
The Big Answer:
In the case at hand, Achashverosh could not revoke his own
decree because he had a contract with Haman, for which Haman paid
consideration of 10,000 pieces of silver. So Achashverosh was not
free to simply revoke the decree that he had made.
Even a contract can be "breached", though, if one is willing
to pay. So why did Achashverosh not revoke his decree and pay back
the contract. Achashverosh must not have been able to afford
paying off the contract. He was hard up for cash as evinced in his
soon instituting a new tax. (He had to pay for that party after
all, and Midrashic sources say he owed his kingship in the first
place to wealth.) In addition, breach may have resulted in his
having to pay damages of "expectation", which would amount to all
the wealth people had expected to plunder from the Jews. This would
be a fairly large amount which he certainly would not want to pay.
However, even if he did not expressly violate the terms of the
contract, he seemingly violated its spirit and was therefore
perhaps guilty of "constructive breach". This is probably why he
killed all of Haman's sons; this way there would be no one to sue
on behalf of his estate. He did not kill Haman's wife Zeresh,
because women in Ancient Persia did not have property rights and
she therefore would not have "standing" to sue on behalf of the
estate.
But could all the people who expected to plunder the Jews sue
for constructive breach? The answer is no - because they were
"third party beneficiaries" to the contract and therefore had no
"privity" to sue. In addition, just in case they could construct
privity to sue, Achashverosh instituted the tax to show then
whatever the general populace might try to sue him for in a "class
action" he could take right back in a general tax.
Res Ipsa Loquitur V'Hamevin Yovin