If Iran did indeed plot to assassinate Saudi Arabia's ambassador to the US, it would be a violation of a treaty it signed in 1978 forbidding “Crimes Against Internationally Protected Persons,” which could escalate the incident to a UN matter, Reuters reports. “This is one of those areas where there’s not really too much fuzziness,” says one professor of international law. “It's very clear that these kind of people (diplomats), they're immune from attack."
The treaty obligates Iran to either prosecute or extradite alleged co-conspirator Gholam Shakuri, who is believed to be in Iran and a member of its Quds Force. If it doesn’t, the US or Saudi Arabia could have Interpol issue an international arrest warrant for Shakuri, or demand arbitration from the Court of International Justice—or even seek action from the UN Security Council. “These are very obvious violations and for the Security Council to do nothing … cheapens the words,” the professor says. (Read more Iran stories.)