When the Senate’s long delayed torture report is finally released – if the new, Republican-controlled Senate releases it at all – the international conversation will rightly focus on the CIA torture program’s stunning strategic and moral failures, and the impunity granted so far to its architects. But the findings of the report, some of which have already been disclosed, should also force a conversation about the military commissions at Guantánamo, because those commissions are designed to mask the very conduct that the report condemns.

When President Bush created the military commissions, their purpose was to ensure the conviction of detainees on the basis of evidence obtained through torture. The due process enshrined in our constitution was essentially replaced by a kangaroo court: the military obstructed defendants’ access to counsel; it restricted their ability to see the evidence against them; and prosecutors were allowed to introduce hearsay evidence as well as statements obtained through coercion and torture.

The military commissions are flawed and unfair at best, with military judges at Gitmo saying as recently as Thursday afternoon that another decade-long case of a CIA “black site” detainee “is going to take months” just to get off the ground. The defence resources afforded inmates are so anemic that the ACLU has spent over $6m to support these defence teams.

No amount of money, however, can fix a system that is unconstitutional and fundamentally defective.

While the commissions’ rules have since been reformed in some important ways by Congress and the Obama administration, justice at Guantánamo remains warped by the America’s legacy of torture. Continuing arbitrary rules and procedures, for instance, all but guarantee the conviction and execution of the five 9/11 defendants awaiting trial, all while allowing the government to keep secret the barbaric torture methods the CIA used on prisoners in secret detention centres.

In 2012, a commission’s military judge allowed the government to censor the 9/11 defendants’ testimony about their rendition, interrogation and detention by the CIA. Government officials claimed any discussion of what happened to the defendants during their arrests or while in custody could reveal intelligence “sources, methods and activities” – including, not coincidentally, evidence that CIA interrogators waterboarded defendant Khalid Shaikh Mohammed 183 times in March of 2003.

Torture is so endemic to the prosecutions undertaken by the US military commissions that the military designed and built a special courtroom just to limit any outside access to unredacted testimony given at the commission: court and legal observers are relegated to “censorship chambers” attached to the courtroom, where they can only view the proceedings behind soundproof glass with a 40-second audio delay.

And just to make certain that no one will hear if the defendants or their lawyers mention torture outright, the military judge and commission’s security officer have a button to unilaterally cut that audio feed when they believe discussion might veer into dangerous territory. When the government can silence the truth about its own crimes in a single click, it’s the very negation of justice.

But there’s still time for President Obama to do what he pledged to do from his first day in office: shut down the military commissions and transfer the 9/11 defendants to the United States to be tried in civilian court, which the world sees as fair and impartial. The president has the power to choose who will stand before the military commissions, and he has the power to dismantle them for good.

Shutting down the Gitmo commissions would be an appropriate and necessary response to the Senate report’s findings on torture. Now that we are beginning to acknowledge the full scope of the torture program, the United States can’t justify continuing to prosecute prisoners in a system that was designed to whitewash the torture program and prevent the public from learning of its full scale.

The president should also take the death penalty off the table for the 9/11 defendants – regardless of whether those prosecutions take place in the commissions or in federal court. Imposing the death penalty on prisoners who’ve been tortured while in US custody would be entirely unconscionable, but declining to impose the ultimate punishment in these prosecutions would be a way – though an imperfect one, as others have noted – to acknowledge the taint of torture that will linger over the legal proceedings.

The US constitution guarantees that even those accused of the most monstrous crimes will be afforded a fair trial. The founders learned that lesson from one of their own, John Adams, who decided at great risk to his career and reputation to defend the British soldiers accused of murdering five Americans in the Boston Massacre. Afterward, he remarked that it was “one of the best pieces of service I ever rendered my country”.

The military commissions fall disastrously short of the rights the constitution guarantees the accused. If allowed to continue, the United States will have quite openly sacrificed its founding principles to cover up torture. President Obama has always known that the right thing to do was shut down Guantánamo and its military commissions. The Senate torture report gives him one more reason – and the perfect opportunity – to finally follow through on his promise.