The recent debate over whether enhanced interrogation techniques elicited the intelligence that led to Osama bin Laden underscores the need for Congress to more thoroughly evaluate counterterrorism tactics.

Shortly after bin Laden’s death at the hands of Navy SEALs, former Bush administration officials — including Vice President Dick Cheney, Deputy Assistant Attorney General John Yoo and National Security Agency and CIA Director Michael Hayden — took to the airwaves to claim the outcome vindicated their enhanced interrogation program. Sens. Dianne Feinstein (D-Calif.) and John McCain (R-Ariz.) and then-CIA Director (now Secretary of Defense) Leon Panetta rejected that conclusion, citing contradictory evidence.

Regardless of whether one thinks enhanced interrogation techniques led to bin Laden’s death, this episode raises other questions.

Why hasn’t some Congressional inquiry investigated and rendered a verdict on the effectiveness of EITs long ago?

What is the purpose of Congress’ oversight role if not to evaluate (and regulate as necessary) such controversial and consequential executive activities?

We believe the record is clear that EITs played little or no role in finding and dispatching bin Laden. To date, none of the champions of EITs has offered a clear example of the techniques producing valuable information. Instead, as in Hayden’s most recent piece, they like to conflate “all information gained through any CIA interrogation” (much of which is valuable) with “information gained through EITs” (none of which has been proved to be valuable).  Harsh techniques were used on less than a handful of detainees, and — as investigative reports, leaked documents and former interrogators who witnessed the use of the techniques explain — those detainees offered their most useful information to interrogators who developed rapport with them and learned what made them tick.

But regardless of how one perceives the evidence for or against the effectiveness of EITs,  it is perplexing that Congress has not settled the matter through anything like a scientific evaluation of the tactics.

The same complaint can be made for most counterterrorism tactics.

While Congress has occasionally charged the Government Accountability Office, various inspectors general or the Congressional Research Service with investigating the legality of specific counterterrorism  tactics or claims that they have been abused, it has done little to promote the kind of sustained and systematic inquiry into the effectiveness of counterterrorism practices that could not only settle questions about EITs but also improve our ability to combat terrorism more generally.

As Congress debates the defense authorization and appropriation bills,  Members should make sure the nation is investing not just in military construction projects but also in learning how we can best deal with the evolving threats posed by nonstate groups and individuals.

They should make sure that regardless of whether Congress expands the Authorization for Use of Military Force, it expands the role social scientists and researchers can play (working with the Congress and in universities and civil society) to ensure that the most optimal practices are being used to track, disrupt and dismantle terrorists’ networks and campaigns.

Promoting scientific evaluation of security practices will require Congress and researchers to work closely with government agencies often housed in cubes of dark glass and steel, literal “black boxes.” Concerns about secrecy must be adequately and smartly addressed.

As the debate over enhanced interrogation techniques has proved, too little about what works in counterterrorism is settled knowledge — in or out of government.

Congress is the only entity with the constitutional authority and the wherewithal to really change that fact.

With the Arab Spring and the death of bin Laden likely altering the future shape of the threat posed by terrorists, now is a particularly opportune time to expand our capacity to clearly and methodically evaluate the challenges we are up against and how best we can face them down.

Nick Adams is director of the Science of Security Program at the Breakthrough Institute and a sociologist at the University of California-Berkeley, where he is completing his Ph.D. dissertation. Ted Nordhaus and Michael Shellenberger are the founding principals of the Breakthrough Institute, based in California.