U.S. Attorney General Eric Holder on Monday said the Justice Department has not decided whether to file federal civil rights charges against George Zimmerman in the 2012 killing of 17-year-old Trayvon Martin. Zimmerman, a volunteer neighborhood watchman who shot and killed Martin in an incident that captured national interest, was acquitted of murder charges in July. But the Justice Department could still pursue a federal civil rights case. Holder said the agency’s investigation is under way. “I'm not sure exactly how much longer that will take, but we will get to a point where we are able to make a...