Zacarias Moussaoui didn't pull the proverbial trigger of the 9/11 attacks. But was his involvement in the terror plot so extensive that he deserves to be executed?
That's a key question before the 12 jurors charged with deciding his sentence. As they weigh aggravating and mitigating factors, their answer may depend in part on how much they believe Mr. Moussaoui's own testimony about the role he played in the jetliner strikes.
Many legal analysts predict that he will receive a death sentence. And some go so far as to suggest that despite the government's sloppy and questionable tactics in the case, appeals court judges will uphold any capital sentence.
For Moussaoui, this outcome may, ironically, guarantee what he would call an exalted status - one he did not enjoy within Al Qaeda, even on the eve of the 9/11 attacks, according to his own testimony. He boasted to the jury that he was assigned to fly a jetliner into the White House - an objective that would have been the terror group's most important target on that day. Yet he also admitted that he was on a kind of probation within the terror group at the time. So why would Al Qaeda trust such an important objective to someone the plot masterminds considered unreliable?
Some say perhaps Moussaoui was playing a game with the US Justice Department when he took the stand and admitted involvement in 9/11 after having repeatedly denied it. He wants to become a martyr, they suggest.
But there is a problem.
Many terrorism experts question the veracity of Moussaoui's testimony. They say the evidence suggests he was training for a second wave of attacks after 9/11, not the 9/11 attack itself.
Federal prosecutors had initially labeled Moussaoui the 20th hijacker. But after interrogations overseas - including of a key architect of the attacks - the government dropped that notion and relied instead on a theory that Moussaoui was partly responsible for the massive death and destruction on 9/11 because he knew enough about Al Qaeda's plans to thwart the attack had he only been truthful with FBI agents following his arrest in August 2001.
Some legal analysts considered the government's approach a creative stretch - until Moussaoui took the stand.
Despite significant questions about the reliability of Moussaoui's testimony, federal prosecutors appear prepared to ride their windfall all the way into closing arguments calling for Moussaoui's death.
"I think the government wanted to find somebody they could hold responsible, but the people who perpetrated the 9/11 attacks are all dead," says Joshua Dressler, a law professor at Ohio State's Moritz College of Law in Columbus, Ohio. "They have this individual who is obviously anti-American and who would do harm to this country if he had the opportunity. And he becomes the person who is going to pay the consequences for things that really he didn't do."
The US Supreme Court helped pave the way for this possible outcome in a 1987 decision in which the high court declared that those who are involved in a murder other than the triggerman can be executed for their involvement in the crime. In that case, Tison v. Arizona, the majority justices said that even though a murder defendant didn't pull the trigger, or even intend that the killing take place, he could nonetheless be put to death if he acted with reckless indifference to human life and was a "major" participant in the crime.
If Moussaoui's testimony is accurate and the real 9/11 plan included a jetliner attack on the White House with Moussaoui at the controls in the cockpit, his involvement would indeed be "major" and his deadly intent would be crystal clear. But what if his testimony is not accurate? Does the second-wave scenario also elevate him to major participant status in the 9/11 plot?
It is clear under federal and constitutional law that the death penalty isn't restricted to a triggerman, says Sara Sun Beale, a Duke University law professor and author of a highly regarded legal text, "Federal Criminal Law and Its Enforcement." But what is less clear, she says, is how significant a role a defendant had to play in a particular crime to justify a death sentence. "I can't think of any clear precedents that would show us how far those links can be stretched," she says.
In a dissent in the Tison case, then-Justice William Brennan warned that extension of capital punishment to criminal accomplices carries risks of corrupting the justice system.
There may be a strong desire to seek out someone to punish "when the killings stir public passion and the actual murderer is beyond human grasp," Justice Brennan wrote. "Yet punishment that conforms more closely to such retributive instincts ... is tragically anachronistic in a society governed by our Constitution."
Those who carried out the 9/11 attacks died with their victims. Some, who planned the attacks, have been interrogated overseas under questionable circumstances and thus are unlikely to ever face trial in a US courtroom.
Legal analysts say Moussaoui offers the government an opportunity that doesn't exist with those who were heavily involved in 9/11.
"In this case, if we separate out Moussaoui's own testimony and look at what the government produced to connect him to 9/11, his involvement from the government's aspect is extraordinarily limited and very thin," Professor Dressler says.