AUGUSTA - It took U.S. Sen. Susan Collins three years to shepherd postal reform through Congress and onto the president's desk.

It took just one signature to apparently turn the technical bill into something else: permission for the president to open sealed mail without a warrant.

The White House disputes that any new power has been sought, but questions about President Bush's actions have led to calls for more congressional oversight of Postal Service policies.

On Dec. 20, Bush signed the Postal Accountability and Enhancement Act, with Collins, dressed sharply in a red suit among the dark blues, blacks and grays of her colleagues, standing at his shoulder.

What Collins didn't know then - and didn't find out about until Thursday when a story appeared in the New York Daily News - is that Bush had attached a signing statement to the law, adding his interpretation of how it should be applied.

The Daily News scoop left Collins' office trying to find out what it all meant.

In the signing statement, which is public record, Bush appears to contradict the wording of the actual law. He "claimed sweeping new powers to open Americans' mail without a judge's warrant," Daily News reporter James Meek wrote Thursday.

According to the signing statement, the executive branch can open sealed mail under "exigent circumstances, such as to protect human life and safety."

"The Collins-Carper postal reform bill, which was recently signed into law, represents the most sweeping reforms to the U.S. Postal Service in decades, but does absolutely nothing to alter the protections of privacy and civil liberties provided by the Constitution and other federal laws," Collins said Thursday in a prepared statement.

A significant overhaul of the postal service was a big accomplishment for Maine's junior senator because, as she said at the time, "the U.S. Postal Service is the linchpin of a $900 billion mailing industry, providing nine million jobs nationwide, including 38,000 right here in Maine."

Given the complexity of the issue and the various interests involved, it took a lot of effort by Collins and U.S. Sen. Tom Carper of Delaware to pass the law.

The circumstances and procedures under which the government may search sealed mail are well-defined, Collins said.

"The Foreign Intelligence Surveillance Act of 1978 and our federal criminal rules require prior judicial approval before domestic sealed mail can be searched," she said in a prepared statement. "Under limited circumstances when there is an immediate danger to life or limb or an immediate and substantial danger to property, our postal inspectors have the authority to search a sealed package or envelope. This occurs, for example, when wires protruding from a package, odors escaping from an envelope or stains on the outside of a package indicate the contents may constitute such a danger."

In the morning briefing at the White House, Bush spokesman Tony Snow said that the signing statement was about clarifying the law, not broadening presidential authority.

"What the signing statement indicates is what present law allows, and making it clear what the provisions are within present law in terms of dealing with some of these items," Snow said in response to a reporter's question.

"This is not a change in the law," Snow said. "This is not new. It is not as was described in one paper as a 'sweeping new power' by the president. It is, in fact, merely a statement of present law and present authorities granted to the president of the United States."

Despite the message coming out of the White House, the signing statement was enough to put civil libertarians on guard.

"We think signing statements are a tool the president uses to try to subvert U.S. law," said Shenna Bellows, the executive director of the Maine Civil Liberties Union. "The president is supposed to enforce the laws that Congress passes."

Anthony Romero, the executive director of the American Civil Liberties Union, likened the intent of the statement to the warrantless surveillance of telephone calls and Internet communications, which the president has also approved.

"Given the president's dismal record of violating the privacy rights of Americans, we must question whether he is authorizing the opening of mail without a warrant in violation of the Constitution and laws enacted by Congress," Romero said.

The ACLU has filed a Freedom of Information Act request seeking information about the intent of the statement and is asking Congress to investigate.

Collins, for her part, is also hoping for answers.

"I have long had concerns about the president's broad use of signing statements to raise questions about the executive's intention to comply with legislation approved by Congress and signed into law by the president," Collins said in a news release. "And it is my hope that the administration will clarify its intent with this recent statement."