Newdow and other plaintiffs say they want to watch the inaugural either in person or on television. As atheists, they contend, having to watch a ceremony with religious components will make them feel excluded and stigmatized.
"Plaintiffs are placed in the untenable position of having to choose between not watching the presidential inauguration or being forced to countenance endorsements of purely religious notions that they expressly deny," according to the lawsuit.
Among those named in the lawsuit are Chief Justice of the United States John Roberts, who is expected to swear in the new president; the Presidential Inauguration Committee; the Joint Congressional Committee on Inauguration Ceremonies and its chairwoman, Sen. Dianne Feinstein of California; and the Armed Forces Inaugural Committee and its commander, Maj. Gen. Richard Rowe Jr.
The two ministers scheduled to participate in the ceremony also are named: the Rev. Rick Warren and the Rev. Joseph Lowery. The document includes a quotation from Warren on atheists: "I could not vote for an atheist because an atheist says, 'I don't need God.' "
Newdow told CNN that he didn't name President-elect Barack Obama in the suit because in addition to participating as a government official at the ceremony, he possesses rights as an individual that allow him to express religious beliefs.
"If he chooses to ask for God's help, I'm not going to challenge him," Newdow said. "I think it's unwise."
Newdow said that as a member of a racial minority, Obama should have respect for atheists, who also are members of a minority.
Newdow said religious references in the inauguration ceremony send a message to non-believers.
"The message here is, we who believe in God are the righteous, the real Americans," he said.
Newdow said it's unconstitutional to imply that atheists and others are not as good.
He acknowledged that his suit is unlikely to be successful.
"I have no doubt I'll lose," he said, adding that he hoped to eventually succeed through appeals and hoped future inauguration ceremonies would exclude religious references.