Once the bodies were found the investigation intensified. The fact that someone had already talked gave the agents leverage to use on various Ku Klux Klansmen within the area. Eventually two men came forward and agreed to testify to the facts surrounding the murders. Now the question was how to proceed. The FBI had acquired all the information, but murder charges could only be brought by the state. In the end an unusual course was taken. The federal government decided to prosecute the murderers under an 1870 law making it a federal crime to conspire to deprive individuals of their civil rights. The maximum penalties were a five thousand-dollar fine and up to ten years in prison, but it offered the only likelihood of a successful prosecution, given the reluctance of local officials to pursue murder charges.

False Starts.

Late in 1964 the government...