On this Fourth of July, it is somehow fitting that we are awash in a sea of important Supreme Court decisions addressing fundamental constitutional issues. Yet, the ruling that may prove to be the most critical of all seems to be garnering the least attention.

I'm referring to Cheney v. U.S. District Court for the District of Columbia, the case in which two public interest groups are striving to gain access to the records of President Bush's energy task force, chaired by Vice President Cheney. Ten days ago, the high court sent the case back to the Court of Appeals for the District of Columbia with instructions that essentially rewrote 50 years of judicial history.

You're probably thinking: What on earth is she talking about? In the last week and a half, we've had decisions on U.S. citizens who are considered enemy combatants and on the rights of Guantanamo Bay detainees. How could an opinion with which the justices put off making a final decision until after the presidential election possibly be so important? Well, think again. With this decision, the Supreme Court has just re-landscaped the constitutional terrain between the White House and the judiciary in a manner that seems to hand off a portion of the judiciary's power to the executive branch.

Understanding the difference between "executive privilege" and "executive powers" is the key to understanding the Cheney decision. So bear with me here. "Executive privilege" is the doctrine under which the president contends that he does not have to turn over, in judicial or other proceedings, evidence concerning his performance of his executive branch duties. "Executive powers" are those powers assigned in the Constitution to the president, rather than Congress or the courts.

In a nutshell, here's what happened: Throughout the Cheney litigation, the administration took the novel position that it would not assert "executive privilege" as grounds for withholding the information sought by the Sierra Club, the liberal environmental group, and by the conservative Judicial Watch. Instead, the White House insisted on relying on the somewhat amorphous (some might even say squishy) notion that the task force documents were protected because the vice president was operating pursuant to his "executive powers."

The administration therefore took the position that if it did not assert executive privilege and the vice president was carrying out the duties conferred on the executive by the Constitution, the documents relating to those duties did not have to be turned over -- and the courts did not have the right to review that decision. But is it indeed the case that the courts cannot review an executive decision to withhold documents produced in the performance of executive duties? Until the Supreme Court's ruling 10 days ago, constitutional scholars would have said the answer was clear. If an administration wanted to withhold information pertaining to domestic policies in the midst of a lawsuit, its only viable option was to invoke "executive privilege" and take its chances with judicial review, meaning the courts would decide whether the privilege was properly claimed.

Only in those relatively rare instances where the shrouded information related to defense or international affairs could an administration avoid invoking executive privilege (and the consequent judicial review). Those areas were perceived to fall so squarely within a president's powers that no other branch, including the judiciary in the context of a lawsuit, had the right to second-guess the president. (And since suits pending in our courts are much more likely to relate to domestic matters than defense or foreign affairs, a president who wanted to withhold documents typically had to assert the privilege and await a judicial determination.)

It comes as no surprise that the administration did its darnedest in the Cheney case to avoid asserting executive privilege. But, the District Court and the Court of Appeals apparently read the same cases that I did, and therefore reached the same conclusion: Energy is a domestic matter, and it was therefore incumbent on the vice president to invoke executive privilege and submit the information being withheld to the courts for review. Alternatively, he could simply produce the information to the plaintiffs.

The high court clearly disagreed. In one quiet little line, on the 20th page of a 21-page majority opinion, the seven justices in the majority undid decades of evolving doctrine with this: "[the Court of Appeals] labored under the mistaken assumption that the assertion of executive privilege is a necessary precondition to the Government's separation-of-powers objections." Translation: The administration need not invoke a doctrine that would subject the decision to withhold information to judicial review, even regarding matters of domestic policy.

With barely a nod to precedent (except to explain why the Nixon tapes case, which came out the other way, wasn't similar at all), the majority endorsed the administration's position on this point, pretty much lock, stock and barrel. If the White House wants to withhold information when members of the public seek it, the White House may simply do so. No claim of executive privilege is required. And if there is a process for judicial review in the absence of a privilege claim, I'm not seeing it.

The history of the doctrine of executive privilege, coupled with the current administration's reputation for a lack of openness, casts this decision in a particularly ironic light. Although the evolution of executive privilege is generally believed to have begun with President Dwight Eisenhower's 1954 dispute with a congressional committee investigating the Defense Department, most of the contextual evolution of executive privilege and executive powers occurred during the Nixon years, particularly in the Watergate era.

When President Richard Nixon, who was renowned for his penchant for secrecy, sought to assert an absolute, non-reviewable executive privilege as justification for withholding his Oval Office tapes, his efforts were thwarted in 1974 by a Supreme Court that retorted that the president could not remove from the Court the "province and duty . . . to say what the law is." Even so, Chief Justice Warren E. Burger was careful to note, the decision requiring Nixon to turn over the tapes would likely have been quite different if the subpoenaed materials had contained "military or diplomatic secrets," for which "the courts have traditionally shown the utmost deference" to the president.

Almost exactly 30 years later, the court has reached the opposite conclusion regarding the right to withhold documents by an administration that some consider as secretive as Nixon's. I find this particularly ironic, given the anecdotal evidence that no administration has shrouded itself in executive privilege more frequently, or for a broader variety of reasons, than has the current one. One feels compelled to ask: Of all times, why is the court doing this now?

As Boston Globe reporter Anne E. Kornblut wrote on Feb. 11, 2002, "During his first year in office, Bush has delayed the release of presidential papers from the Reagan White House, imposed limits on public access to government documents, refused to share revised data from the 2000 Census, and shielded decades-old FBI records from scrutiny."

Make no mistake: The White House's assertion of executive powers in the Cheney case is novel. No previous president, when confronted with a judicial demand for documents related to a domestic issue, has ever responded with a claim of executive power. That the Supreme Court has accepted that assertion is stunning. The majority has excused the administration from complying with the only process that assures the courts the right of review when an administration refuses to honor a subpoena and has accepted the argument that the vice president was acting under his executive powers, a realm into which the judiciary cannot intrude. Against the backdrop of this decision, the question now is this: If the vice president is ordered by the lower courts to reveal documents, will the administration honor such orders?

Or, has the balance of power in the realm of executive secrecy now truly shifted to a new final arbiter?

Joan Lukey is a senior partner at Wilmer Cutler Pickering Hale and Dorr LLP in Boston. In the 1980s, as a Massachusetts special assistant attorney general, she represented the administration of Michael Dukakis in its unsuccessful efforts to establish executive privilege in the commonwealth.