The history of congressional hearings is, to say the least, a checkered one. Members of Congress have abused the hearing process to foment witch hunts, as Senator Joseph McCarthy did with the Tydings Committee to investigate the loyalty of State Department employees. More recently, members of both parties have staged hearings to play the scold, inveighing against the allegedly violence-inciting lyrics of, among others, Twisted Sister, Tupac Shakur, and Marilyn Manson—all while doing precious little to curb the sale of actual guns. At their best, however, congressional hearings can play a salutary role, shining a light on neglected public interests and exposing corporate fraud and government malfeasance. The Pecora Committee used its subpoena power to haul banksters in front of Congress in the wake of the 1929 stock-market crash, leading to the passage of the Glass-Steagall Act. McCarthy himself was undone by the 1954 Army-McCarthy hearings. And Henry Waxman’s 1994 grilling of tobacco executives exposed to all the world that companies like Philip Morris knew about the harmful effects of smoking and manipulated the nicotine content of their products to keep consumers addicted.

With last week’s 11-hour interrogation of Hillary Clinton, the House Select Committee on Benghazi brought congressional hearings to high farce. The nakedly partisan GOP fishing expedition revealed nothing new about the attack on the US compound in Libya that 32 previous hearings—10 more than the 9/11 attacks apparently warranted—hadn’t already uncovered. Outclassing her opponents, Clinton calmly batted away irrelevant inquiries about, for example, her e-mail correspondence with Sidney Blumenthal. What she wasn’t forced to do is answer probing questions about the 2011 US-led intervention in Libya and her role in planning it.

That’s a shame, because four years after the death of Moammar El-Gadhafi, Libya is a wreck. Two rival governments compete for power and territory alongside the forces of ISIS and various tribal and Islamic militias, some armed with US weapons intended for rebel groups. Libya’s economy and institutions have collapsed, and medicine, fuel, and food are all in short supply. What could the United States have done to prevent this fiasco? Why did the administration commit to intervention against bipartisan rebukes from Congress? What were its goals: to protect civilians, as President Obama claimed at the time, or regime change? And if the latter, what regime did Secretary Clinton imagine would take the place of Gadhafi’s? A Congress that took its oversight duties seriously would have asked these questions long ago.

Congress should also take up Representative Keith Ellison’s call for increased oversight regarding drone strikes. Earlier this month, The Intercept published an eight-part series based on leaked documents that confirm what has long been suspected: Drone strikes are highly inaccurate—during a five-month period in Afghanistan, almost 90 percent of those killed were not the intended targets—and the Pentagon knows this. On what legal basis is this assassination program conducted? What kind of intelligence is required to authorize a strike? And how exactly does the chain of command work?

Congress also has an obligation to call current and former executives of Exxon to testify about what is perhaps the greatest corporate fraud in all of human history. Twin investigations by the Pulitzer Prize–winning InsideClimate News and the Los Angeles Times have revealed that Exxon knew as early as 1977 that burning fossil fuels would cause climate change. It then spent the next few decades in a massive disinformation campaign meant to discredit the conclusions reached by its own scientists. How far up did this cover-up go—and what are the human and environmental costs? A Congress of, by, and for the people would have called such a hearing within days of these revelations. Instead, hours after the Benghazi hearing, Congress created a select committee to re-investigate Planned Parenthood.