ST. LOUIS — The ACLU filed a lawsuit yesterday against a southeast Missouri city after a former library worker claimed she was wrongly disciplined when she refused to work at an event to promote a Harry Potter book due to her religious beliefs.

The woman, Deborah Smith, is a Southern Baptist who believes the Harry Potter books "popularize witchcraft and the practice of the occult," said Anthony Rothert, legal director for the American Civil Liberties Union of Eastern Missouri.

Smith worked as a part-time library assistant at the Poplar Bluff Public Library for more than a year, but said she could not take part in a July 20, 2007, event to mark the release of Harry Potter and the Deathly Hallows the next day. In the wildly popular books by J.K. Rowling, children have magic powers. Library employees were expected to dress as witches and wizards for the event, Rothert said.

He said Smith was suspended for 10 days without pay when she refused to work at the event, which was held outside of the library's normal hours. Smith, who has a pacemaker, did tasks like checking out library patrons' books and answering phones prior to the dispute.

Upon her return, she said her hours were cut and she was given more labor-intensive tasks, like emptying out a book drop-off box, he said. Rothert said she quit on her doctor's recommendation.

The lawsuit filed in federal court in Cape Girardeau yesterday alleges violations of her First and 14th Amendment rights, including her right to free exercise of religion. It seeks unspecified damages. It also names the library's director, Jacqueline Thomas, as a party being sued. A listed number could not be located for Thomas after business hours.

There was no response to phone messages left for Poplar Bluff's attorney in time for this story.

"Government employers must respect individuals' religious beliefs," Brenda Jones, executive director of the ACLU of Eastern Missouri, said in a statement. "Federal law requires accommodation of religious beliefs so that every citizen's religious liberty is safeguarded."

The ACLU said Smith filed complaints with the federal Equal Employment Opportunity Commission and the Missouri Commission on Human Rights, and that both agencies issued her notices of her right to sue this spring.