It took more than two years of negotiations between military prosecutors and defense attorneys to reach a plea bargain resolving the case against Khalid Sheikh Mohammed and two other Guantanamo detainees accused of orchestrating the Sept. 11, 2001, terrorist attacks that killed nearly 3,000 people and launched the U.S. into a two-decade war in Afghanistan. It took only two days to rip up the deal after its announcement Wednesday sparked a firestorm of criticism from Republicans accusing the Biden administration of coddling terrorists. Late Friday, Defense Secretary Lloyd Austin issued a terse memo canceling the agreement prosecutors had concluded was the best—and perhaps only—way to resolve a case marred by allegations that the U.S. tortured the defendants. The deal would have kept the defendants in prison for life, taking the death penalty off the table in exchange for guilty pleas.

Denise LeBoeuf, an American Civil Liberties Union lawyer representing Mohammed, said defense counsel were stunned by Austin’s move. “We’re disappointed that the government would breach a legal agreement that provides some judicial finality and some measure of justice for the 9/11 family members, the government, and the defendants,” she said. “This was negotiated over 27 months with full knowledge, taking into account that 9/11 family members’ views at every step, until the secretary reversed,” she said. Families of the victims are divided over the case, with many contending that death is the only appropriate punishment for the crime. Others oppose capital punishment, while others still agree with prosecutors that a plea bargain is the best way to resolve the case.

Although the defendants have at times claimed responsibility for the Sept. 11 attacks, the prosecution was hamstrung by the brutal treatment Central Intelligence Agency interrogators inflicted on the defendants at so-called black sites overseas. The CIA objected to having courts rake over that treatment—which former President Barack Obama and other authorities have described as torture—undercutting the detainees’ ability to mount a full defense. That alone could lead a court, or a military jury, to take the death penalty off the table. Even if a military jury returned the death penalty, it could be vulnerable on appeal, under Supreme Court precedent that sanctions prosecutors for government conduct that “shocks the conscience,” as a 1952 precedent put it.

Seeing no end to proceedings and little chance of securing death sentences in light of the torture allegations against U.S. interrogators, the chief prosecutor, Rear Adm. Aaron Rugh, concluded that a plea bargain was the best way to end the case, nearly a quarter-century after the suicide hijackings crashed jetliners into New York’s World Trade Center, the Pentagon and a Pennsylvania field.

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