When did Ban Ki-moon become the world’s top lawyer?

As the head of a world organization that leaves most power with its member states, the United Nations Secretary-General has to navigate all sorts of political minefields. One of the trickiest is deciding when and how to deploy the language of international law. The UN Charter describes the Secretary-General as the organization’s "chief administrative officer." He is not a judge and is not empowered to make decisions on international law; his pronouncements on the subject have no direct legal effect.

Recognizing their professional and political limitations, secretaries-general have typically shied away from making pronouncements on divisive questions of law. That tradition of reticence makes a series of recent statements by Ban Ki-moon all the more notable. This week, the Secretary General condemned a new Israeli decision on settlements:

UN Sec.-Gen. Ban Ki-moon on Tuesday joined a growing chorus of condemnations to the Israeli government’s decision to convert three West Bank outposts into settlements, saying he was "deeply troubled" by the decision.

"The Secretary-General reiterates that all settlement activity is illegal under international law," a statement from Ban read, adding that the decision was a "provocation" and contrary to Israel’s obligations under the Road Map.

The week before, Ban addressed South Sudan’s occupation of the disputed town of Heglig:

Mr Ban urged the south to withdraw its forces immediately to stop border clashes spiralling into a war.

South Sudan has issued a statement to say it is not interested in war with its northern neighbour.

It says Heglig is rightfully part of South Sudan and it does not want the north to use it as a base for attacks.

But Mr Ban said the seizure of Heglig "is an infringement on the sovereignty of Sudan and a clearly illegal act".

Late last year, the Secretary General waded boldly into the dispute over whether NATO had exceeded its legal authority in Libya:

"Security Council resolution 1973, I believe, was strictly enforced within the limit, within the mandate," Ban told reporters in New York. "This military operation done by the NATO forces was strictly within (resolution) 1973."

"I believe this is what we have seen, and there should be no misunderstanding on that," he said.

Some of this law-talk can no doubt be chalked up to Ban’s increased latitude as a second-term Secretary General. But it may also be the product of the times. As has been widely noted, international politics has become increasingly legalized. In the last several decades, a half dozen new international tribunals and courts have formed. Yet on many of the most hotly disputed international questions, there is still no quick or ready way to resolve legal disputes. The International Court of Justice–designed to be the UN’s legal arm– has limited jurisdictional reach and, in any case, moves at a glacial pace. In this environment, it’s awfully tempting for the Secretary General to hang out his shingle.