Fort Hood, Texas (CNN) -- The Army psychiatrist defending himself against charges that he killed 13 people in a shooting rampage at Fort Hood, Texas, concluded his case on Wednesday without calling a single witness.
Maj. Nidal Hasan ended days of speculation over whether he would take the stand with three words: "The defense rests."
Closing arguments were scheduled to begin Thursday morning before the case is handed to a military jury, which will determine whether Hasan is guilty of 13 counts of murder and 32 counts of attempted murder in connection with the November 5, 2009, attack.
It was unclear if Hasan, who faces the death penalty if convicted, planned to deliver a closing statement.
Hasan's decision not to offer a defense was an anticlimactic end to the testimony portion of a court-martial where prosecution witnesses, primarily survivors, painted a horrific picture of what unfolded inside the processing center during the attack.
Inside the courtroom, the liaison for the family members of those killed handed out packages of Kleenex ahead of the day's proceeding.
As they have nearly every day of the trial, some of the wives and mothers of the 12 soldiers and one civilian killed had their eyes fixed -- some in a cold stare -- on Hasan.
There is no question about whether Hasan carried out the shooting rampage as he took credit for it at the outset of the trial, telling the jury of 13 senior officers during opening statements that the evidence will show "I was the shooter."
The judge, Col. Tara Osborn, has refused to allow Hasan to argue "defense of others," a claim that he carried out the shootings to protect the Afghan Taliban and its leaders from U.S. soldiers.
Much has been made of Hasan's defense or, as his stand-by attorneys have said, the lack of it. The judge declined a request by Hasan's attorneys to drop out of the case. The attorneys argued that Hasan was helping the prosecution put him to death.
There may be something to that claim.
The judge barred Hasan from pleading guilty at the start of the court-martial. Under military law, defendants cannot enter guilty pleas in capital punishment cases.
In recent weeks, he has leaked documents through his civilian attorney to The New York Times and Fox News that appear to offer a glimpse of Hasan's justification for carrying out the attack.
The documents included a mental health evaluation conducted by a military panel to determine whether Hasan was fit to stand trial.
"I don't think what I did was wrong because it was for the greater cause of helping my Muslim brothers," he told the panel, according to pages of the report published by the Times.
He also said, according to the documents: "I'm paraplegic and could be in jail for the rest of my life. However, if I died by lethal injection I would still be a martyr."
Military prosecutors called 89 witnesses and submitted more than 700 pieces of evidence before resting their case, hoping to show that the American-born Muslim had undergone what they described as a progressive radicalization.
They have argued to the jury that Hasan, who was scheduled to deploy to Afghanistan, did not want to fight against other Muslims and believed he had a jihad duty to kill as many soldiers as possible.
Over the course of 11 days, prosecution witnesses painted a horrific picture of the shooting rampage that began inside the deployment center, with a number recounting how the gunman rose from a chair, shouted "Allahu Akbar" -- Arabic for "God is the greatest" -- and fired more than 146 rounds in the room.
The prosecution witnesses called Tuesday described the final minutes of the attack, a police shootout that ended with the gunman shooting a police officer before he was shot. Hasan was paralyzed from the chest down.
The final witness called by the prosecution, Dr. Tonya Kozminski, testified about what Hasan told her would happen to the Army if he were deployed.
"The last thing he said ... 'They will pay," Kozminski said.