A Texas school district is being sued by the American Humanist Association (AHA) for allegedly emphasizing Christian religion, Fort Worth Weekly reported.

The group filed the suit against the Birdville Independent School District on behalf of a former student, Isaiah Smith, who has clashed with school officials before.

According to the lawsuit, the district regularly opens its school board meetings by choosing students to deliver Christian prayers. The suit argued that this is an endorsement of the Christian faith by the board, making Smith feel unwelcome.

The practice, the suit stated, also creates "a coercive atmosphere where attendees, particularly children, are pressured to participate in the prayers."

The AHA intervened on behalf of Smith in November 2013, after he was suspended for protesting his bullying at the hands of other Birdville High School students by carrying a Bible around school after ripping several pages out from the Book of Leviticus. Smith said at the time that the students were targeting him because he is gay. The suspension was ultimately expunged from his record after the AHA intervened.

The district also came under criticism a year earlier for allowing students to say on-field prayers before football games, calling it a "limited public forum" that did not represent officials' views.

The AHA said in a statement that the district also allows schools to take overnight trips to churches and display "Christian iconography" in their classrooms, making it a "repeat offender of the separation of church and state."

"By beginning meetings with Christian prayers, the school board is sending a message that those of minority faiths, and of no faith, are not welcome," AHA executive director Roy Speckhardt said.