She already had diplomatic immunity, which is sacrosanct within the Law of Nations. In the old days, the Mongols sacked Baghdad and executed its emir by rolling him up in a carpet and trampling him to death with their horse after he killed one of their diplomats. Similarly, the Mongols also chased another potentate over a thousand miles before capturing and killing him by pouring molten silver down his throat for killing another one.
Messing with diplomats is not something you just want to do.
She worked at the consular and had no recognized immunity from the State Department.