The state’s largest group dedicated to separation of church and state has joined a lawsuit to stop religious services at the inauguration of President-elect Barack Obama. The lawsuit, now joined by Minnesota Atheists, is being initiated by Michael Newdow, a separation of church and state advocate.

At issue are the scheduled events involving the Rev. Dr. Joseph Lowery, a prominent civil-rights pastor, and the Rev. Rick Warren, whose statements about same-sex marriage and abortion have created an uproar among progressives.

“Under the Establishment Clause, Plaintiffs have a right to view their government in action without being forced to confront official endorsements of religious dogma with which they disagree. This is especially the case when that dogma stigmatizes them in the process,” reads the lawsuit. “Being forced to confront such religious dogma as the price to pay for observing a governmental ceremony is a substantial burden upon Plaintiffs’ rights of Free Exercise as well.”

The suit says that the planned religious services will impinge on the freedoms of some Americans. “One cannot freely live as an adherent to a religious ideology when the government uses its ‘power, prestige and financial support’ to impose a contrary religious doctrine while such individuals are observing its ceremonies.”

August Berkshire, president of Minnesota Atheists, issued a statement Tuesday, stating the organziation is “pleased to accept a personal invitation from Michael Newdow to be a plaintiff in this lawsuit. The swearing in of a president is a secular event. The oath of office is in the U.S. Constitution and it contains no religious references. It is unfortunate that while Barack Obama campaigned on a theme of unity, the very act of becoming president will serve to divide Americans along religious lines.”

The lawsuit is expected to be filed this week in United States District Court for the District of Columbia.