The family of Ahmed Mohamed, the Muslim teenager who was handcuffed and suspended from his suburban Dallas high school last year after his homemade digital clock was mistaken for a bomb, sued school officials on Monday, saying they had violated his civil rights.

The episode at MacArthur High School in Irving, Tex., in September became a political flash point and President Obama invited him to the White House. But after the freshman was subjected to fevered criticism and threats, Ahmed and his family moved to Qatar.

The lawsuit, which seeks unspecified monetary damages, names the school district, the city of Irving and Daniel Cummings, the school principal. It accuses the school district and Mr. Cummings of discrimination, and said the Irving Police Department arrested him without probable cause.

As a result, the lawsuit says, Ahmed has been vilified and subject to conspiracy theories, lies and hatred that “no kid in this country should have to endure.”