Four New York men who were questioned or patted down by police are seeking a halt to a city “stop and frisk” policy that they say unlawfully targets people on the basis of race.

David Floyd, Lalit Clarkson, Deon Dennis and David Ourlicht, four black men who claimed they were stopped and questioned or frisked by New York police without reasonable suspicion, are set to begin trial today in Manhattan federal court of their claim that officers routinely violate the rights of black and Latino New Yorkers.