WASHINGTON -- David Nelson is a law-abiding 34-year-old lawyer from Belleville, Ill. But he says the government treats him as if he's a threat to commercial aviation who shouldn't be allowed on a plane.

Nelson says he believes his name appears on the government's "no-fly list," people deemed too dangerous to board commercial flights. For Nelson, it's a case of mistaken identity: he's not the David Nelson the government believes is a threat.

Still, he says he's been delayed at airports dozens of times as government officials questioned him.

Nelson is among seven people whom the American Civil Liberties Union brought together in a class-action lawsuit filed Tuesday against the Transportation Security Administration, which administers the list.

"Few would line up in sympathy for a trial lawyer delayed for a few minutes at the airport every time he wants to hop on the plane," Nelson said in an interview. "But surely it affects individuals of color disproportionately, individuals of Arab descent or who practice the Muslim religion, and it's very much those people on my mind when I volunteered to be a named plaintiff."

His colleagues in the lawsuit include a retired minister, a college student, an Air Force master sergeant, a human rights activist and two ACLU employees.

The lawsuit, filed in U.S. District Court in Seattle, claims the "no-fly list" violates airline passengers' constitutional protection against unreasonable searches and seizures and their right to due process. The civil rights group says the government has not put enough safeguards in place to ensure people with similar names aren't treated with suspicion.

"You can't force the same innocent people over and over and over again to shoulder the burden of our lack of decent intelligence," said Reginald Shuford, the ACLU's lead attorney on the case.

TSA spokesman Mark Hatfield said he couldn't comment on the case but is confident the "no-fly" list is legal.

"Our standard procedures and our systems in place, those we've created and those we've inherited, have all stood the legal tests they've been subjected to so far," he said.

The TSA administers two lists: "no-fly" and "selectee." Those on the "no-fly list" are not allowed to board a commercial aircraft. Those on the "selectee list" must go through more extensive screening before boarding.

Federal law enforcement and intelligence agencies recommend to the TSA who gets put on the lists, but little else is known about them. The government does not disclose how many people are on the lists or how people qualify to get on or off, nor does it confirm any names on the lists.

Hatfield said the problem of confusing innocent people with those on the lists points to the need for a broader TSA program that can conduct computerized background checks of all airline passengers and to rank them according to their risk of being terrorists.

"If we can create a system, and we believe we've architected one, that has a very accurate identification component, we're going to eliminate the vast majority of misidentification," Hatfield said.

The ACLU and other privacy advocates oppose the program, called the Computer Assisted Passenger Prescreening System, or CAPPS II.

"It doesn't make sense to replace this deeply flawed program with a larger program that will capture innocent people in larger numbers," ACLU spokesman Jay Stanley said.

The other plaintiffs in the lawsuit are:

--Michelle D. Green, 36, an Air Force master sergeant.

--Alexandra Hay, 22, a Middlebury College student.

--John Shaw, 74, a retired Presbyterian minister from Sammamish, Wash.

--Mohamed Ibrahim, 41, coordinator with the American Friends Service Committee.

--David C. Fathi, 41, senior staff attorney with the ACLU National Prison Project in Washington.

--Sarosh Syed, 26, special projects coordinator at the ACLU in Seattle.

------

On the Net

Transportation Security Administration: www.tsa.gov

American Civil Liberties Union: www.aclu.org

To see the ACLU's complaint: www.aclu.org/SafeandFree.cfm?ID15419&c272