JACKSON, Miss. — Civil rights advocates say harsh disciplinary practices at many Mississippi schools lead to children being expelled and even incarcerated for minor infractions, policies that disproportionately affect minorities.

A joint report by groups including the ACLU and NAACP says the problems are more widespread than just the city of Meridian, where the Justice Department has filed a suit claiming officials are running a ‘‘school-to-prison pipeline’’ for minor infractions.