The exchange marked the first time Hasan has questioned a witness to the shooting.
And earlier Monday, Hasan asked that the definition of "jihad" be adjusted. Prosecutors didn't object, and jurors were told that "under Islam, the central doctrine that calls on believers to combat enemies of the religious belief."
Such moments have been rare during the trial, during which Hasan has rarely spoken. In fact, the judge — once again — urged Hasan on Monday to forgo representing himself and to allow trained attorneys to take over.
Osborn told Hasan she believed he would be better off with a lawyer who knew the rules for military trials, such as when to raise objections and how to spot issues that could be cited on appeal.
"Remember when I told you that I thought you would be better off with a trained lawyer, who would know the rules for courts martial. ... You know that," the judge said.
"Repeatedly," Hasan replied.
"You still wish to proceed pro se?" she asked.
"I do," Hasan said.
Military defense attorneys ordered to help Hasan have accused him of trying to secure himself a conviction and death sentence. Hasan has denied the claims — but he could face the death penalty if convicted.
Prosecutors indicated on Friday that they had between 15 and 25 witnesses left, though it wasn't immediately clear how Monday's ruling blocking much of their motive evidence would affect their case.
The ruling also frustrated Reed Rubinstein, an attorney representing victims and their relatives in a civil lawsuit against the U.S. government. He said only in an "alternative universe" could the emails excluded by Osborn be irrelevant.
He also blamed the government for dragging out Hasan's case and making some evidence too old to be considered. In Monday's ruling, the judge said prosecutors couldn't cite Hasan's interest years ago in conscientious objector status and his past academic presentations because both were too old and irrelevant.
"The reason for that is the procedural pretzels the government has tied itself in to protect Hasan," Rubinstein said, noting that the trial was originally delayed because of a fight over whether Hasan could keep his beard, which violates military policy.
Rubinstein said that even if Hasan were found guilty, a conviction that comes without prosecutors introducing Hasan's alleged ties to terrorists in the criminal trial would leave a distaste for survivors of the attack.