IT'S JUST BEEN REVOKED.
So...rather than do another 'Foreign Service on Screen' post, I thought I'd take a minute to examine this sticky little issue of diplomatic immunity. What is it, how do you get it, and why do we have it at all?
According to the Vienna Convention, all people accorded diplomatic status are inviolate in their persons and exempt from all laws and taxes of the host nation. This means they cannot be arrested, searched, or threatened.
Pretty neat, huh? This does NOT mean, in practice, that you have carte blanche. Rob banks, drive 90 in a 30 mile zone, shoot up heroin in the street and you might find yourself in trouble. For one thing, diplomatic immunity doesn't stop bullets. If someone acts in self-defense and shoots you, you're still dead. Even before it gets that serious your diplomatic privileges are still dependent on the host government and can be revoked at any time. Persona non grata exists for this very reason.
Diplomatic immunity was created as a means of protecting the messenger. If countries were afraid that their representatives would be harmed, they wouldn't be able to convey their messages clearly and accurately. When the Spartans threw the Persian ambassador down a well, their next ambassador altered and softened his message, and it became impossible for the Spartans to send their own ambassador to Xerxes.
I've never seen Lethal Weapon 2, but any diplomat who went around killing people would be taken down very quickly. Add to that, the diplomat in question was a consular diplomat. That doesn't necessarily mean he adjudicated visas; it means he was attached to a consulate rather than an embassy. This means that he didn't even have full diplomatic immunity; it only extended to actions related to his work duties. Shooting cops probably wasn't covered.
Do people abuse diplomatic immunity? Very much so. Most famously, in the millions of dollars in unpaid parking tickets around the United Nations. Annoying as that may be, it is a necessary evil to protect the international system.