President Trump, Russian Foreign Minister Sergei Lavrov, left, and Russian Ambassador Sergey Kislyak at the White House. (Russian Foreign Ministry Handout/European Pressphoto Agency)

Steve Vladeck is a professor of law at the University of Texas School of Law and co-editor of Just Security. His Twitter handle is @steve_vladeck.

Now that President Trump has all but confirmed that he shared classified information with senior Russian officials, the conversation has shifted from “whether it really happened” to “whether the president can really do that.” The conventional wisdom suggests that, while disclosing such information may have been a Really Bad Idea, the president does not face any legal problem because he has the ultimate authority to declassify national security information.

In fact, the legal situation is much more complicated. A number of laws may well prohibit what Trump did, and Congress may have the power to subject even a sitting president to such restrictions. No one should expect grand jury indictments to be forthcoming. (Spoiler alert: They won’t be.) But the classic Nixonian argument — when the president does it, it’s not illegal — doesn’t apply in this situation.

First, even if the president does have unfettered authority to declassify whatever national-security secrets he chooses, it’s pretty clear that this is not what happened here; whatever he told the Russians is still secret, as evidenced by The Post’s initial decision, at the government’s urging, not to publish the details of the underlying revelations. Whatever the scope of the president’s power, he presumably has to actually exercise it in order to invoke it as a legal justification. He did not do that. Instead, the most charitable reading of what the president did was to authorize the Russian officials to receive still-classified information, a move that implicates a different array of legal authorities.

Second, many of the relevant criminal statutes don’t actually turn on whether the wrongly disclosed information is classified or not. For example, the relevant section of the Espionage Act — which the Obama administration used so controversially to prosecute leakers — prohibits the knowing disclosure of “information relating to the national defense” to “any person not entitled to receive it” so long as the discloser “has reason to believe [the information] could be used to the injury of the United States or to the advantage of any foreign nation.”

Likewise, the federal conversion statute, which has also been used to prosecute leakers, prohibits the conversion “to . . . the use of another” of any “thing of value of the United States.” If Trump had, for example, handed copies of photographs to the Russians that they could not otherwise have obtained, it’s not at all clear why that language wouldn’t be satisfied, too — even if the photos were not actually classified.

Third, and perhaps most important, it is not nearly as clear as commentators tend to assume that the president’s inherent constitutional power over national security information is not subject to limits — such that any attempt by Congress to restrict the president’s authority would be unconstitutional.

Supporters of the president’s power in this area typically invoke the Supreme Court’s 1988 decision in Department of the Navy v. Egan, which held that the president’s “authority to classify and control access to information bearing on national security . . . flows primarily from this constitutional investment of power in the President and exists quite apart from any explicit congressional grant.” But Egan concerned the president’s power to act on this topic without congressional authorization. It did not reach the altogether different and far more serious question of whether Congress has any role to play in national security classification — and who would prevail in an interbranch dispute over classification.

Although Congress of late has largely abdicated any authority or responsibility for national security classification, that hasn’t always been the case. Thus, the Atomic Energy Act of 1954 includes detailed legislative rules governing the classification of nuclear secrets (many of which are still on the books). The Freedom of Information Act, signed in 1966, gives courts the power in some circumstances to review government claims that requested materials cannot be disclosed because they contain classified information, and to overturn such claims in contexts in which they are not consistent with the underlying statutory rules.

Of course, the scope of Congress’s power over national security classification is an entirely academic exercise; even after this latest imbroglio, this Congress is not likely to revisit control of national security secrets anytime soon. And even if the president did transgress some statutory prohibition, it’s not as if he realistically faces criminal prosecution for doing so. It therefore makes plenty of sense that the discussion of Trump’s patently indefensible disclosures has shifted to why it’s so dangerous as a policy and political matter — assuming away the significance of any legitimate legal objections.

But now more than ever, it is incumbent upon all of us — the press, the public and all those who would seek to hold our government accountable — to tread carefully before assuming that the president is vested with special powers to ignore rules that bind the rest of us. As with much of the commentary emanating from the White House these days, there are reasons to believe that it’s just not true.