The report I saw said it was Massachusetts law that comes into play. The law states along the lines of: Once a new Senator is elected and qualified in the special election, the appointed Senator's term is ended.
Since a Senator was elected and he is qualified, Kirk's term should have ended at the closing of the polls on election night.
Dems, being Dems they will use anything to push their agenda, but the law seemed pretty clear, Kirk should be out.
You don’t think the laws of a mere-—state-—would concern the gods of the Senate, do you?
State law doesn't trump federal law, nor Senate rules for that matter. In this instance, the law is clear - it is COMPLETELY left to the Senate who they seat, and when they seat them.