sentences:  A group of UNC students along with Aptheker and Williamson filed a lawsuit in U.S. federal court, and on February 20, 1968, the Speaker Ban Law was struck down.In 1968, only a year after its schools became fully integrated, Chapel Hill became the first predominantly white municipality in the country to elect an African American mayor, Howard Lee.Lee served from 1969 until 1975 and, among other things, helped establish Chapel Hill Transit, the town's bus system.