Dylann Roof faces nine charges of murder in his bloody, racially motivated rampage at a black church in Charleston, South Carolina. He already faces the death penalty for his crimes, and should he be convicted, execution seems to be the most likely outcome (eventually).
There is no legal need to the federal government to get involved in the court case. But you don't get publicity by doing nothing, do you? So, in effect, the Department of Justice is apparently going to file additional charges against Roof for the purpose of expressing its opinion that what Roof did was really, really bad. From the New York Times:
Mr. Roof, 21, already faces nine counts of murder in state court and could face the death penalty there. But Justice Department and F.B.I. officials have said the Charleston shooting was so horrific and racially motivated that the federal government must address it.
He was also charged with killing someone while obstructing religious freedom, which is eligible for the death penalty.
South Carolina doesn't have hate crime laws, so here we are. The other laws that South Carolina has are more than sufficient to handle the brutality of Roof's crimes, hate-motivated or not. There isn't a gap here. There isn't an injustice that is going to be left unaddressed by the state courts. The Department of Justice is using the law to express how it feels about Roof's motivations. That's an awful way to make prosecutorial decisions.
Granted, in this case, nothing likely will or can come of it because Roof is already doomed. But it's important to remember that not all situations where the Department of Justice comes stomping in are so cut-and-dried. Recall that federal prosecutors used hate crime laws to throw a group of Amish people into federal prison over a religious fight that resulted in men's beards being forcibly shaved off. A federal appeals court overturned the convictions last year.