In an uncoerced confession in his new memoir, Decision Points, former President George W. Bush proudly admits that he personally signed off on the waterboarding of Khalid Shaikh Mohammed in 2003. Former Vice President Dick Cheney made the same admission in a televised interview shortly before he left office. In one sense, this is nothing new. It had long been reported that the CIA’s use of what the Bush administration euphemistically called "enhanced interrogation techniques" had been approved at the highest levels of the administration. But now both Bush and Cheney have publicly admitted to specifically signing off on the CIA’s torture tactics. Their direct personal admissions now seal the case against them.

What case, you might ask? There is in fact no criminal or civil case against the former president or vice president for these actions. And both men no doubt felt comfortable admitting they had authorized what the world recognizes as torture because they believe they are politically immune from being held accountable. Even before the midterm elections, Barack Obama had insisted that he wanted only to look forward, not backward. With a strengthened Republican Party after the elections, it is even less likely that Bush or Cheney will be held accountable by the Obama administration. On November 9 the Justice Department announced that no criminal charges would be brought against the CIA agents who destroyed videotapes of the torture interrogations; that part of the cover-up, it seems, has succeeded.

But Bush and Cheney are not immune. In fact, the United States is legally obligated by the Convention Against Torture, a treaty we helped draft, and have signed and ratified, to investigate any credible allegations of torture by a person within US jurisdiction. And if the United States does not take action, other nations are authorized to do so, under the principle of "universal jurisdiction," which treats torture as so heinous that its perpetrators can be investigated and prosecuted by any country if their own country fails to take corrective action.

Chile’s former President Augusto Pinochet found this out the hard way. After flying to London for medical treatment, he was served with an arrest warrant issued by a Spanish magistrate investigating him for, among other things, authorizing torture. Pinochet argued that he was immune from such action as a former head of state, but Britain’s highest court rejected that plea, and Pinochet was placed under arrest. He was eventually sent back to Chile on medical grounds, but he spent the last years of his life there fighting criminal charges arising out of his acts as president.

Investigating and arresting the former president of Chile is one thing. Investigating and arresting the former president and vice president of the United States would be another matter altogether. No doubt Bush was relying on just that calculation in admitting his guilt in his memoir. And it may be that Bush and Cheney are deliberately admitting their crime at a time when they know they will not be prosecuted, in hopes of putting the issue behind them and providing cover to those below them who also approved of the crime. How can we prosecute anyone lower down when the president and vice president have admitted to giving their approval?

But the principle of universal jurisdiction, combined with our government’s failure to take any steps toward accountability, means that Bush and Cheney can be investigated and prosecuted anywhere in the world. They may feel confident that President Obama will not have the temerity to hold them accountable, but it’s not clear they should be confident about the rest of the world. Two investigations of US complicity in torture are already pending in Spain, where Pinochet was initially investigated. And Poland has recently opened a criminal investigation of torture at a CIA "black site" there. Bush and Cheney may want to limit their vacations to the homeland for the foreseeable future.

But from our standpoint, it’s not enough that some other nation might take up what we seem incapable of. It is ultimately our responsibility. The two highest members of the previous administration have openly admitted to criminal wrongdoing. And not just any crime—a war crime and a violation of one of the world’s most universally recognized legal prohibitions. (Bush and Cheney insist that waterboarding is not torture, but that argument is frivolous; if subjecting a human being to the panic of drowning by pouring water over his mouth and nose so that he cannot breathe is not torture, it is difficult to know what that term encompasses.)

As American citizens, it is our obligation to insist that Bush and Cheney be held accountable. I don’t expect a criminal prosecution. But accountability can come in many forms. The most realistic response, and I think the most responsible, would be for Congress or the president to impanel a blue-ribbon, bipartisan commission to investigate the use of torture and issue a report on its legality. If we don’t declare these actions illegal, we will simply reinforce the already widely held and deeply corrosive impression around the world that the United States insists on the rule of law for others but disregards it for itself whenever it is politically inconvenient.