Attorney General Eric Holder says his Justice Department is going after WikiLeaks' Julian Assange. At first glance, it seems like a straightforward case. Almost half of the 250,000 internal State Department cables Assange has published are classified, either at the confidential or the secret level (no top-secret documents are included), and rarely does the target of a criminal investigation commit his alleged crime so publicly.

Holder knows it will not be easy, however. He realizes that as much as we may condemn Assange's actions, they were not obviously criminal. Indeed, just the other day Holder found himself defensively insisting that this is a real investigation, not mere "saber-rattling."

The first challenge, of course, will be to find Assange, who is in hiding both because of this investigation and because he faces rape and sexual molestation charges in Sweden - charges he denies and claims are part of an effort to shut him down. Complicating matters, most extradition treaties do not allow extradition for "political offenses," and Assange is sure to argue that subjecting U.S. foreign policy to public scrutiny is a political act.

But even if the Justice Department finds him, arrests him and extradites him, its work will be far from over. The U.S. government has never successfully prosecuted a media entity for a leak. It is typically much easier to bring such cases against the government officials who do the leaking, because they sign nondisclosure agreements surrendering many of the legal protections they otherwise would enjoy.

Just recently, the department tried to expand the scope of its leak prosecutions to individuals outside the government, in a test case involving two lobbyists for the American Israel Public Affairs Committee, a pro-Israel group. I represented one of the lobbyists, who were indicted for leaking information that had been disclosed to them by high-level U.S. officials during discussions about the Middle East. The men were wiretapped for five years. They were investigated for another year. They were then indicted and spent the next three years skirmishing with the prosecution. And then, on the eve of the trial, the Justice Department dropped the charges.

Why are leak cases so tough?

There is no general law making disclosure of classified information a crime.



What law did Assange violate? It will surprise many that there is no statute making it illegal to reveal classified information. There are statutes that criminalize the disclosure of very specific types of classified information, such as the identity of a covert operative (think Valerie Plame) or "codes, ciphers or cryptographic systems." But there is no catch-all law that simply says, "Thou shalt not disclose classified information."

Indeed, when Congress tried to enact such a statute, President Bill Clinton sensibly vetoed it. His reason: The government suffers from such an overclassification problem - some intelligence agencies classify even newspaper articles - that a law of this sort would end up criminalizing the disclosure of innocuous information. And even that vetoed statute would have applied only to government officials, not to private individuals or journalists.

Instead, prosecutors in the Assange case, like the prosecutors in the AIPAC case I handled, would resort to the Espionage Act of 1917, an archaic, World War I-era statute that prohibits "willfully" disclosing "information relating to the national defense." According to Judge T.S. Ellis in the AIPAC case, this means that the prosecution must prove, among other things, that a defendant knew that the information he was disclosing was potentially damaging to national security and that he was violating the law.

Here, Assange can make the department's case especially difficult. Well before publishing the cables, he wrote a letter to the U.S. government, delivered to our ambassador in London, inviting suggestions for redactions. The State Department refused. Assange then wrote another letter to State, reiterating that "WikiLeaks has absolutely no desire to put individual persons at significant risk of harm, nor do we wish to harm the national security of the United States."

In that second letter, Assange stated that the department's refusal to discuss redactions "leads me to conclude that the supposed risks are entirely fanciful." He then indicated that WikiLeaks was undertaking redactions on its own.

The First Amendment still matters.



The First Amendment, of course, protects both freedom of the press (yes, WikiLeaks is the press) and freedom of expression. That is one reason Holder is not investigating this newspaper or the New York Times, even though both are publishing extensive details from the cables: It is the Justice Department's practice to refrain from bringing leak indictments against traditional media outlets.