WASHINGTON - A jury has opened the way for the only person convicted over the September 11 attacks to be executed.
It decided unanimously that the lies of Zacarias Moussaoui were responsible for at least one death on the day that the United States was attacked by al Qaeda.
The same jury will now hear testimony from the relatives of those who died that day, before deciding whether he should actually be sentenced to death.
Moussaoui, 37, the so-called 20th hijacker, was in custody at the time of the attacks on New York and Washington, but prosecutors argued that by lying to FBI investigators he had actively prevented them from stopping the September 11 plot to seize four civilian airliners.
"By this verdict, the jury has found that death is a possible sentence in this case," said a court spokesman, Ed Adams, outside the federal courthouse in Alexandria, near Washington.
Moussaoui, a French citizen, prayed in silence as he waited for the verdict. He refused to stand up to hear the decision and said: "You'll never get my blood, God curse you all."
The tortuous trial will turn into yet another twist on Friday when the jury members will listen to testimony as to whether he should be executed.
September 11 victims' relatives will describe the human impact that resulted from his actions; Moussaoui's court-appointed defence lawyers will call experts to argue he is schizophrenic.
If the jury decides against the death penalty he will be sentenced to life imprisonment.
Moussaoui had previously pleaded guilty to conspiring with al Qaeda though he initially denied being part of the September 11 plot. Some observers believed that it would be hard for the prosecution to make the case for the death penalty on a conspiracy case, especially after an FBI field agent testified that his repeated warnings about Moussaoui's possible involvement with al Qaeda had been ignored by senior officials.
But then Moussaoui appeared to seal his fate when he took to the stand and claimed that he was due to fly Flight 93 into the White House. This was the plane which ultimately crashed in a Pennsylvania field.
The Bush Administration has been desperate to bring this trial to a conclusion, partly perhaps, for symbolic reasons. At the same time, given Moussaoui's often-changing story, it is doubtful that any clearer picture has been learnt about the plot, or indeed whether he genuinely was to have been involved.
Hamilton Peterson, whose parents died on Flight 93, said: "I feel confident in light of Moussaoui's own testimony that it is the right decision and look forward to ... the final determination of execution."