How rare are online threat prosecutions?

In an essay in the New York Times Magazine on Elonis v. United States, the Facebook threat case to be argued Monday involving the interstate threat statute, Emily Bazelon writes that the rarity of online threat prosecutions is a reason to be wary of the defense's First Amendment claims:

The truth is that even when intent to do harm seems obvious, online threats are rarely prosecuted. Citron looked at the federal law that is the basis for the Elonis case and found that it has been enforced fewer than 50 times, online and off, over the past eight years. Stalking laws, domestic-violence advocates say, aren't enforced much, either.

If the Supreme Court requires evidence of a speaker's intent to harm in true-threats cases, it could give the police and prosecutors one more reason not to bring them. Maybe that's simply the unavoidable consequence of a broad interpretation of the First Amendment. Let's be clear, though, that such an approach to free speech doesn't come free. The choice in this case between points of view - Anthony's or Tara's - mirrors another choice, between types of personal liberty. His or hers.

I don't think that's right. Elonis was prosecuted under the interstate threat statute, 18 U.S.C. § 875(c). The Bureau of Justice Statistics keeps stats on how often different federal crimes were charged. Running the numbers for § 875(c) for the last eight years the numbers are available - 2005 to 2012 - shows 242 cases closed involving § 875(c). Some of those are non-Internet cases, like old-fashioned telephone threats, but my sense is that more and more are online threats. And that's just § 875(c): Other Internet threats are charged under different federal statutes, such as 47 U.S.C. § 223(a)(1)(E). Plus, many other threat cases are state cases prosecuted under state threat laws.

Internet threat prosecutions aren't the most common prosecution of online conduct. But they're not as rare as Bazelon's essay suggests, and my sense is that at least some prosecutors take these cases pretty seriously.

(Full disclosure: A few months ago, I provided a very small amount of assistance to co-blogger John Elwood, counsel of record for Elonis, in the Elonis case.)

UPDATE: I fiddled with the post a bit shortly after putting it up.