(June 6) - Republican and Democratic House leaders join forces to protest the FBI search of a congressman's office. The Senate Intelligence Committee demands fuller briefings from the CIA. The Supreme Court hears a landmark case challenging presidential war powers.

After five years of a concerted White House campaign, there are tentative signs that Congress and the courts are beginning to push back against what has been the greatest expansion of presidential powers in a generation or more.

Those pushing back include some congressional Republicans and conservative jurists who have been among President Bush's chief allies. The efforts surely would intensify if Democrats won control of the House or Senate in November's elections - and with it the power to convene hearings and issue subpoenas.

"You ask, 'Is the tide shifting?' and I say, 'Maybe, maybe,' " says Senate Judiciary Chairman Arlen Specter, R-Pa., who has pushed for stronger congressional oversight of intelligence operations. "If you ask me if I still feel like a lonely voice, I would say that I feel like a member of a small chorus."

Some examples:

-- House Speaker Dennis Hastert and Democratic Leader Nancy Pelosi, usually at war, issued a joint statement denouncing the FBI search last month of Rep. William Jefferson's congressional office as a violation of the separation of powers between co-equal branches of government. Their ultimatum that seized documents be returned is now the subject of negotiations with the Justice Department, which is investigating bribery allegations against Jefferson, D-La.

-- The Senate Intelligence Committee voted 9-6 two weeks ago to demand that the administration notify all members of the committees about intelligence operations. The administration has bypassed the intelligence committees to inform only eight congressional leaders about such sensitive programs as the National Security Agency's warrantless-surveillance operation.

-- Congressional Republicans and Democrats in March upended plans for a Dubai-owned company to take over some U.S. port operations, forcing the firm to promise to transfer the operations to a "U.S. entity." Outraged lawmakers weren't convinced when the president dismissed their national-security concerns as unfounded, and they weren't deterred when he threatened the first veto of his presidency to protect the deal.

-- The White House and Congress continue to jockey over who has the last word on the treatment of terror suspects. Congress approved an amendment banning torture over the objections of Vice President Cheney. Bush signed the legislation in December but issued a "signing statement" in which he reserved the right to waive the ban, which he suggested violated his constitutional authority as commander in chief. Senate Armed Services Chairman John Warner of Virginia and Arizona Sen. John McCain of Arizona, both Republicans, then issued a joint statement vowing "strict oversight to monitor" implementation of the law.

The dispute has delayed the release of a new Army Field Manual on interrogation this spring. The Los Angeles Times reported Monday that several senators say the proposed manual sets standards for terror suspects that violate the congressional ban.

The 'Nature of Our System'

White House spokeswoman Dana Perino says the administration has been able to meet Congress' concerns without conceding presidential powers. She notes that administration officials agreed to brief Intelligence Committee members last month about the NSA operation, reported in The New York Times in December, which includes wiretapping calls within the United States without warrants if one of the participants is abroad. The administration calls it the Terrorist Surveillance Program.

"There have been - and always will be by nature of our system - conflicts between Congress and the White House on the limits of executive power," Perino says. "But far from clashing, the two branches have worked well together on very difficult cases and generally made accommodations on issues, like the Terrorist Surveillance Program."

It's true that Congress generally hasn't used or even threatened to use its most potent weapons in a confrontation with the White House, such as issuing subpoenas or cutting off funding for programs.

Still, Bruce Fein, a Justice Department official in the Reagan administration, says Congress' attitude toward the White House is toughening a bit. "We're seeing, maybe, the embryonic stages of drawing the line and saying: 'Here. No more,' " he says.

In the courts, too, some judges in recent months have been more willing to scrutinize Bush's assertions of presidential power.

Judge J. Michael Luttig of the Fourth Circuit Court of Appeals, who had been on Bush's short list of possible Supreme Court picks, last fall wrote a key opinion endorsing the administration's argument that the president could order Jose Padilla, a U.S. citizen and suspected terrorist, to be held indefinitely in a military brig without charges.

But when the administration abruptly decided to charge Padilla in civilian court - apparently to avoid a possible Supreme Court reversal - the judge objected and tried to stop the transfer. Luttig, who resigned from the bench last month, warned of a "substantial cost to the government's credibility before the courts."

The Supreme Court is expected to rule this month in Hamdan v. Rumsfeld, another case that could test presidential powers. Lawyers for Salim Ahmed Hamdan, Osama bin Laden's former driver, are challenging the administration's plan to put prisoners at Guantanamo Bay in Cuba on trial for war crimes in special military tribunals.

At issue: Does Bush's claim of presidential war powers override the protections of the Geneva Conventions?

Some historians say a pattern seen after previous threats to the nation's security - during the Civil War and World War II, for instance - may be repeating itself now that five years have passed since the terror attacks on Sept. 11, 2001.

"In the first few years after a crisis emerges, the courts tend to be very deferential to the White House," says Phillip Cooper of Portland State University in Oregon, who studies separation of powers. "But what tends to happen is after two or three years of deference, then the courts may begin to take a hard look at what's going on ... and remind the administration they don't have carte blanche."

On Saturday, the American Bar Association's board of governors voted to establish a bipartisan task force to investigate whether Bush has gone beyond his constitutional authority in asserting a right to ignore provisions of new laws. Bush has issued more than 750 "signing statements" - more than all previous presidents combined - that state his interpretation of new laws and sometimes declare that they infringe on his presidential powers.

For 30 Years, a Cheney Cause

Even before 9/11, Cheney had made restoring presidential authority a priority. As White House chief of staff for President Ford, Cheney found himself dealing with laws passed in the wake of the Vietnam War and the Watergate scandal that constrained presidential authority. The 1973 War Powers Act, for one, restricted a president's authority to launch military action without congressional approval.

Later, as a Wyoming congressman, Cheney argued that Congress was "abusing its power" when it barred the Reagan administration from funding the Nicaraguan contras. The administration's efforts to evade the law by funneling profits from secret arms sales to Iran reflected "mistakes in judgment and nothing more," according to a minority report he helped draft.

Now, as vice president, Cheney has been in a position to resist and even reverse efforts by Congress to restrain the executive. In the administration's first months, the energy task force he chaired went to court to avoid disclosing the names of industry executives it consulted.

Recently, amid the furor over the NSA's warrantless-surveillance program, Cheney took a similarly hard line. "We have all the legal authority we need," the vice president said in an interview on PBS' NewsHour With Jim Lehrer, citing the Constitution and a congressional resolution passed soon after 9/11. And Congress' role? "We said, 'Look, if you've got suggestions, we're happy to listen to them.' "

The Bush administration has taken a series of actions to expand presidential powers: Enabling past presidents and vice presidents to restrict release of their papers after the 12-year period set in law has expired. Refusing to allow aides to testify before Congress about the federal response to 9/11 and to Hurricane Katrina, arguing that might discourage staffers from providing "unvarnished advice" in the future. Asserting wartime powers to ignore federal laws and international treaties when the president says national security is at stake.

"The administration has been very consistent," Cooper says. "At every turn the White House has issued a reading as expansive as possible for its own authority, a reading as narrow as possible of congressional authority, and in some cases pre-empted the courts."

At a rare session with reporters in December, Cheney expressed satisfaction with what the administration has achieved.

"The president of the United States needs to have his constitutional powers unimpaired," Cheney said. "I do think that, to some extent now, we've been able to restore the legitimate authority of the presidency."

'In a Class' With Nixon, Wilson

Bush's actions and Congress' response matter beyond his own tenure at the White House. They set precedents for future administrations and courts, though presidential powers have surged and ebbed through U.S. history.

Legal historian Kermit Hall says Bush is "in a class" with Richard Nixon and Woodrow Wilson during World War I in extending presidential authority. Tom Mann, a congressional scholar at the Brookings Institution, says Bush has exceeded even the expansive view that Franklin Roosevelt took of the presidency during the buildup to World War II.

Analysts credit Bush's ability to prevail in large part to the aftermath of 9/11, which buttressed Americans' backing for a president with the power to battle a shadowy and terrifying foe. In the fiercely partisan climate of Washington, the Republican-controlled House and Senate generally have lined up behind Bush, not challenged him.

"For five years, this Congress has been breathtakingly supine in the face of the most aggressive assertions of executive power we have seen in modern American history," Mann says. Even now, he says, the House "blowback" over the Jefferson search "probably wouldn't have happened if we didn't have a president whose popularity is in the low 30s."

Bush's dismal job-approval ratings have made critics in Congress and elsewhere more willing to confront him. Another factor: As time passes since 9/11, the threat of terrorism remains a potent argument but may no longer automatically trump other issues.

Now, about half of Americans surveyed by USA TODAY/Gallup from Thursday to Sunday say the Bush administration has "gone too far in expanding the power of the presidency." About one-third say it has struck the right balance. Just 14% say it hasn't gone far enough.

Congress' outrage over the search of Jefferson's office hasn't struck a sympathetic chord with the public, though. In an ABC News Poll taken last week, 86% said the FBI acted properly.

Of two dozen letters to the editor to USA TODAY on the issue, many derided Congress for countenancing corruption. Several wondered why lawmakers hadn't shown equal outrage over, say, the warrantless-surveillance program. Not one praised the institution for defending separation of powers.

Even some lawmakers are skeptical about Congress' commitment to the issue. "This is a newfound interest," says Sen. Chris Dodd, D-Conn. "I hope it extends beyond just protecting ourselves."

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