On the 64th anniversary of the landmark Brown v. Board of Education Supreme Court decision, Mr. Estevez, as president of the Latino Action Network, together with about a dozen other plaintiffs, filed a lawsuit against the State of New Jersey on Thursday, calling on it to desegregate its schools statewide.

Not since 1964, when a federal lawsuit forced integration in Alabama, lawyers for the plaintiffs said, has a suit achieved statewide school desegregation.

“The promise of Brown is not being realized in New Jersey,” Mr. Estevez said. “If you look at a lot of the issues we are having right now in our society, it has a lot to do with the fact that people don’t know each other, and don’t interact with each other, and this creates misunderstanding and animosity. And so it’s important as a society, we think, that people be together, and that they learn side by side.”

The school segregation in New Jersey is de facto segregation, not explicit segregation by law, as was the case in the American South before the Brown decision. It stems from a complicated mixture of discriminatory zoning practices in suburbs, poverty and personal choice, the plaintiffs claim. But it is institutionalized by a state law in New Jersey that requires children to attend schools in the municipalities where they live, said Elise Boddie, a law professor at Rutgers University and a founding member of the New Jersey Coalition for Diverse and Inclusive Schools, a nonprofit that organized the lawsuit.

Because neighborhoods and towns in New Jersey are so segregated, that law results in segregated schools. So the suit asks the state to let children cross municipal lines to go to school. It also calls on the state education commissioner to develop a comprehensive, detailed plan suggesting ways to integrate schools.