Is Torture Effective? How Can We Tell?

The Justice Department's release of a secret report on the interrogation techniques used by the CIA in its overseas prisons has renewed the public debate over torture.

The argument for harsh techniques is that the information obtained can prevent future terrorist acts. And this argument makes sense in principle: if imposing pain, suffering, and even the risk of death on one person can avoid pain, suffering and the risk of death for dozens, hundreds, or even thousands, it would seem hard to object.

Yet the case for torture is not convincing. The crucial issue is that the public has zero evidence that torture has in fact reduced terrorism. Those who defend torture have claimed it helps foil terrorist plots, but they have not provided hard data.

Now, one possibility is that revealing information about foiled plots would compromise ongoing national security efforts.

A different possiblity is that the information obtained from torture has had minimal value in preventing terrorism.

My hunch is with the latter explanation. If the CIA had convincingly foiled terrorists acts based on information from harsh interrogations, the temptation to shout it from the highest rooftops would have been overwhelming.

Thus the logical inference is that harsh interrogations have rarely, if ever, produced information of value.

In that case, the cost-benefit evaluation of torture is trivial: it has certain costs, such as inflaming antipathy to the U.S., and no benefits.