WASHINGTON – Four moderate Republican senators, including Maine Sen. Olympia Snowe, have put together legislation that is raising questions about whether information from federal wiretaps started without a judge’s approval can be used in court, as the bill’s chief sponsor favors.

The proposal is aimed at ending the dispute over President Bush’s warrantless surveillance program. But legal and civil liberties experts said Thursday the measure ultimately could cause further controversy about how the information collected is used in terrorism prosecutions.

The Associated Press obtained a draft of bill, which is expected to be introduced soon by Sens. Mike DeWine of Ohio, Chuck Hagel of Nebraska and Lindsey Graham of South Carolina and Snowe.

The senators have said the bill is designed to provide more protection from terrorists attacks. Ultimately, federal judges will decide how the program’s information – obtained without a warrant – is used in legal proceedings, said DeWine, who has spearheaded the legislation.

But David Sobel, general counsel at the Electronic Privacy Information Center, said the use of such information in judicial proceedings would violate the Fourth Amendment’s ban on unreasonable searches and seizures.

“The problem – in this new, strange environment – is that the government would probably claim the circumstances under which this information was collected was classified, and neither the court nor the defendant can look into the circumstances,” Sobel said.