Updated

Defense lawyers in Florida, New York, Ohio and Virginia are considering filing legal challenges on behalf of suspected or convicted terrorists in response to the National Security Agency's wiretapping program.

After the Sept. 11, 2001, terrorist attacks, the Bush administration authorized NSA to eavesdrop without court approval on people inside the United States with suspected ties to Al Qaeda or who may have been planning a terror attack.

Lawyers question the program, saying the government may have withheld information uncovered during wiretaps to get more convictions, according to a report in The New York Times. They say they want to know if any of the information uncovered could have exonerated their clients. They add that they think the government should have stated during court cases involving the suspects that information had been acquired through a wiretap.

Lawyers for convicted terrorist Iyman Faris, of Ohio, who admitted he was part of a failed bomb plot to blow up the Brooklyn Bridge, may file a civil lawsuit against President Bush for ordering what they say was an illegal wiretap against him.

Other lawyers for convicted terrorists, such as the Lackawanna Six, the six men from Lackawanna, N.Y., who were sent to prison on terror-related charges, may also file legal challenges. The report says the lawyers want to find out if wiretaps were used by the government to uncover evidence to use against the six men.

The White House has defended the wiretapping program, saying it has been only used on people with suspected ties to Al Qaeda and terrorism. Calls monitored by the NSA involved one person domestically in the United States and one person overseas, the administration says.

It "is a limited program ... designed to monitor calls from very bad people to very bad people, who have a history of blowing up commuter trains, weddings and churches. The president believes he has the authority and he does under the Constitution to do this limited program," said Trent Duffy, a White House spokesman.

It is not clear if lawyers would be able to file legal challenges regarding the wiretaps because several clients gave up some of their rights to appeals in plea deals with prosecutors.

FOX News' Molly Henneberg contributed to this report.