In the wake of September 11, the NYPD Intelligence Division set up a secret operation to monitor Muslims in the New York area. Working under the sinister title of the “Demographics Unit” and in collaboration with the CIA, officers attended sermons at mosques, hung out in cafes frequented by immigrants from the Islamic world, and infiltrated Muslim student groups at universities around the Northeast. The idea was that constant surveillance of legal assemblies and activities might provide early warnings of terrorism.

What has the NYPD learned from these tactics? According to the AP’s Adam Goldman (no relation of mine), who received a Pulitizer Prize for revealing the program’s existence last year, the answer is nothing. It’s not just that the secret team didn’t generate any prosecutions. According to the assistant chief responsible for the Intelligence Division, the Demographics Unit hasn’t produced any leads since he assumed command in 2006. That’s six years of domestic spying, often simply on the basis of religion and national origin. And without any results.

The legality of the program is in currently in litigation. But the failure to produce useful intelligence removes its practical justification. Threats of political violence may justify expansions of government powers. When the applications of those powers shows that those threats are exaggerated or non-existent, however, they should by removed or restricted. In short, I can understand why the NYPD and city officials once thought the Demographic Unit was necessary. Now the time has come to shut it down.

Of course, that’s not usually the way things go when it comes to emergency powers. Temporary authority has a way of becoming permanent. Criticism may force the NYPD to conceal the Demographics Unit, perhaps by reconstituting it under a different name or in a different division (it’s already been renamed the “Zone Assessment Unit”). But I fear that the domestic counterpart of the national security state is here to stay.