The Obama administration is reluctant to turn over too many rocks in the Bush administration’s conduct in the War on Terror. Obama has pledged to reach a post-partisan nirvana, and Republicans could condemn any investigation of Bush administration abuse of the republic as a partisan witch-hunt. Also, the Obama administration has a conflict of interest in pursuing investigations and prosecutions against Bush administration officials because now that Obama is president, he may not want to entirely discredit Bush’s precedents, which significantly expanded executive powers.

Yet in the expanse of human history, the existence of republican government has been rare and short-lived by comparison. Even in recent years, when republicanism has spread the farthest, we forget how fragile the experiment is. The stakes are high, and the Obama administration needs to beat down the autocratic precedents left by the previous administration. The only way it can do so is by bringing criminal cases against the high level perpetrators.

This action will not be bipartisan, and the Republicans will rally and claim that Bush and his advisers had good intentions and were just attempting to protect the country in the wake of the September 11 attacks. But the rule of law and constitutional protections are needed most to protect citizens when the government is wielding power to respond to a security crisis. Furthermore, even if you rob a bank and give the proceeds to charity (and the Bush administration’s intentions weren’t even that charitable), you are still guilty of robbing the bank.

Dick Cheney still maintains that the Bush administration didn’t torture anyone. But the vice president’s definition of that term is narrow and, well, tortured. Now that even Susan J. Crawford, the senior Bush administration official in charge of that administration’s kangaroo military commissions, used the "t" word to describe what the administration did to one prisoner, the administration admitted to committing a war crime under international law.

Therefore, a criminal investigation must be launched because the same techniques used on that prisoner  isolation, sleep deprivation, threats by attack dogs, exposure to prolonged cold, and sexual and other humiliations  were used on many other detainees in U.S. custody. And the investigation must involve all relevant officials, including George W. Bush and Dick Cheney.

Astonishingly, Bush recently admitted that he had approved all "extraordinary" techniques used on detainees. The United States has committed illegal acts of torture before  for example, during the Philippine counterinsurgency at the beginning of the last century and by the CIA during the Vietnam era  but this episode is unique and dangerous because the president has admitted that his approval was given. So not only has an administration official admitted a war crime but so has the president. Waterboarding  simulated drowning  was not mentioned by Crawford in the case of that specific prisoner, but the administration has used it on at least three high profile detainees, and it has been considered a war crime for centuries. The interrogation techniques that President Bush admitted approving included waterboarding.

Bush made this admission to boldly defend his record on the subject and probably felt secure in doing so because he feels immune from prosecution. After Gerald Ford’s horrible and unconstitutional precedent of pardoning Richard Nixon even before he could be indicted for his Watergate crimes (the Constitution says that you must be convicted of a crime before getting a pardon), presidents and former presidents couldn’t be blamed for feeling that they were immune from prosecution. This demonstrates the pernicious effects of a bad prior precedent.

And what about investigating and possibly prosecuting Bush for intentionally violating another statute with criminal penalties  the Foreign Intelligence Surveillance Act (FISA). The act said that all spying on people living in the United States will be done with a warrant obtained from the secret FISA court. President Bush deliberately flouted the law and Constitution (the Fourth Amendment in the Bill of Rights implies that warrants are needed for all searches, with no exception mentioned for cases of national security) by not seeking warrants and continuing to ignore the need to do this even after being publicly exposed.

Bush perpetrated this crime and then defended it by reference to an expansive theory of presidential power called the unitary executive theory. Bush believes that in wartime (the legality of this designation is also suspect because, after 9/11, no declaration of war on any party was ever approved by Congress), a president can ignore laws passed by Congress. If the president is allowed to do so without prosecution, it implicitly throws constitutional checks and balances out the window and effectively puts the country on the road to dictatorship.

Of course, violating the Constitution is more serious than violating a law with criminal penalties, but curiously, in America, presidents can get into more severe trouble for violating the law. Thus, although seemingly radical, the only way we can prevent future presidents, including Obama, from capitalizing on Bush’s illegal and unconstitutional precedents to expand executive authority towards dictatorship is to investigate, prosecute, and discredit these abuses of executive power.

The Obama administration, with the complicity of Congress, will probably try to establish a truth commission that will expose, but not prosecute, such crimes. But this is not enough to discredit these vile precedents. Investigation and prosecution are needed, and are now harder for these parties to avoid with Ms. Crawford’s and Bush’s public admissions.