Updated at 6 p.m.: Revised to reflect that the jury would hear more evidence Wednesday.

A Dallas County grand jury heard evidence Monday against a Dallas police officer who shot and killed a 26-year accountant in his own home while he was watching a football game, according to a law-enforcement official with knowledge of the case.

The jurors will hear more evidence in the fatal Sept. 6 shooting when they reconvene Wednesday, the official said. The jurors can vote to indict ex-officer Amber Guyger on a charge of manslaughter, murder or another charge in the shooting death of Botham Jean. They can also decide that Guyger should face no charges.

Attorneys for the Jean family confirmed that grand jury proceedings were underway.

A spokeswoman for the Dallas County District Attorney's office, Kimberlee Leach, declined to comment but said that "the case is ready for a grand jury," she said.

Guyger, 30, was arrested on a manslaughter charge Sept. 9, three days after killing Jean. She told authorities that she mistook his apartment for hers and thought he was a burglar. Her apartment was directly below his unit in the Cedars complex.

Jean's slaying set off weeks of protests in Dallas. Rallies and vigils were held around the country and in St. Lucia, where Jean was born and raised. Guyger is white and Jean was black.

In Texas, manslaughter is considered a reckless act. If Guyger intended to shoot Jean, even if she wrongly thought he was a burglar, murder is the more appropriate charge, Dallas defense attorneys have said.

A charge of murder is punishable for up to life in prison, and a charge of manslaughter could come with a penalty of up to 20 years in prison.

Grand juries typically hear evidence about whether to indict in a particular case for one day, but on rare occasions, that process can stretch longer.

Guyger shot and killed Jean after she finished her shift. She was off-duty but still in uniform and said the door to Jean's apartment was unlocked and ajar. His family disputes that and says Jean wouldn't have left his door open.

Guyger's attorney, Robert Rogers, could not be reached for comment.

The family's attorneys, Lee Merritt and Daryl K. Washington, spoke to reporters at the Frank Crowley Courts Building on Monday, where they confirmed that the Jean family was in Dallas and ready to be called upon to testify. The attorneys said they would be surprised if the grand jury heard evidence beyond Wednesday.

"The family does have probative evidence about Botham's day that day because they spoke to him," Merritt said. "They regularly interacted with him and that may be something the grand jury is interested in hearing about."

It's up in the air whether the family would be called to testify, Washington said.

"If they do call the family in, the family is prepared," he said.

Jean family attorneys Daryl K. Washington, left, and Lee Merritt speak to the media at the Frank Crowley Courts Building on Monday, November 26, 2018. (Shaban Athuman / Staff Photographer)

"The fact that there is even a possibility that this officer may not be charged with murder is something that the whole world is looking at," the attorney said.

Since the shooting, Jean's family hasn't had a normal night's sleep, Washington said.

"This season has been particularly difficult for the family, given that it is going into the holiday season," Merritt said. "It's been three months since Botham was killed in his own apartment, so they've been eagerly anticipating a decision from the grand jury."

Merritt said the family "will reserve comment until after the anticipated indictment."

The Jean family filed a lawsuit against Guyger and the city of Dallas, saying Guyger used excessive force and violated Jean's civil rights.

Guyger was fired Sept. 24, the same day Jean was buried in a cemetery by the sea in St. Lucia.

Jean came to the United States to attend college at Harding University in Arkansas and then worked in Dallas as an accountant. He planned to one day return to the Caribbean island and run for prime minister, his family said.