MARSHALL — A former Marshall Middle School principal is moving forward with an appeal of her lawsuit against the Marshall Public School district.

On Tuesday, attorneys representing Mary Kay Thomas filed a brief in the Eighth Circuit of the U.S. Court of Appeals.

The brief asks the appeals court to reverse a previous court ruling, and send Thomas’s claims of First Amendment and Minnesota Human Rights Act violations back to court for a trial. Thomas was engaging in protected speech and association when she showed support for inclusion of LGBTQ+ students, the brief argued.

Thomas sued the school district and the school board in 2021, claiming that MPS removed her as middle school principal. The school district’s actions came after Thomas refused to take down a rainbow LGBTQ+ pride flag from a display in the middle school cafeteria, and showed support for a student gay-straight alliance, the complaint alleged.

In October, U.S. District Court Judge Patrick J. Schiltz ruled that Thomas’s claims of being discriminated against for advocating for LGBTQ+ students did not fall under the scope of the Civil Rights Act. Schiltz dismissed the claims.

The appeals brief filed this week argued that the court erred in its ruling. It claimed that Thomas was speaking as a private citizen when she showed support for LGBTQ+ students, and that the school district retaliated against her, in violation of the First Amendment.

The brief cited sources like testimony and communications among MPS leaders and personnel to argue that people including school district leaders, a group of middle school teachers and staff, and a group of community members opposed Thomas’s pro-LBTQ+ speech. The brief claims argues these groups wanted to remove Thomas as principal.

Court records said that Marshall Public Schools, members of the school board, and MPS Superintendent Jeremy Williams have until Feb. 20 to file their own brief in the appeal.