The judge in the case said Thursday that she is ordering a new trial because of inconsistencies in the forensic evidence that surfaced this week.
Noah Gaston is accused of shooting his wife, Alicia Gaston, with a shotgun almost three years ago.
Gaston claimed he thought his wife was an intruder but prosecutors argued that he killed her intentionally.
On Tuesday, the second day of the trial, testimony was abruptly postponed when the medical examiner told attorneys that his opinion about the angle of the gunshot wound had changed, suggesting that Alicia Gaston was farther away from her husband than originally thought.
That took both sides by surprise, including family members of the victim, who said they will have to wait even longer for justice.
"To sit there and look at him. It's the worst feeling. Its the worst feeling that he can sit there and Alicia can't," said Barbara Lariviere, the victim's aunt.
"Alicia can't be there to defend herself. He didn't just wound her, he killed her," Lariviere said.
Defense attorneys said that they expect the new trial to start in the fall.
At this point, Gaston is still in custody.