JACKSON, Miss. — Authorities in east Mississippi run a ‘‘school-to-prison pipeline’’ that locks up students for infractions such as flatulence or wearing the wrong color socks, a policy that mainly affects black and disabled children, the US Justice Department said Wednesday in a federal lawsuit.

The lawsuit filed in US District Court in Jackson says officials in the city of Meridian and Lauderdale County have policies that allow students to be arrested and shipped 80 miles to a juvenile detention center without probable cause or legal representation.