The incident has received national attention.
John Hernandez, 24, was in a coma after an altercation with Terry Thompson on May 28 outside of a Denny's in Sheldon.
WATCH: "When I seen the man turning purple, there was no let up."
Investigators said Hernandez was urinating outside the restaurant and that Terry had yelled at him to stop. A physical altercation ensued, and Harris County Deputy Thompson met her husband at the Denny's.
WATCH: "He didn't have to pay with his life."
It's unclear who initiated the fight, but Terry's attorney claims Hernandez threw the first punch. Terry was put into the back of a patrol car that night, but no charges had been filed in the case.
Video released on Monday showed Terry on top of Hernandez with his arm around Hernandez's throat. Witnesses said Chauna was also trying to restrain Hernandez, putting her knee down on his arm.
WARNING: Some viewers may find the following video disturbing
"The video to me is almost by itself enough. You see a person on the ground who is completely immobilized and grunting and moaning. And you see a big guy on top of him choking him and he dies of that choking," said Hernandez family attorney Randall Kallinen.
Hernandez stopped breathing and Chauna administered CPR. Hernandez was taken to the hospital, but died days later.
The sheriff's office announced Tuesday that Chauna was pulled from her patrol responsibilities and assigned desk duty.
Hundreds of people showed up for a march and vigil Wednesday in front of the Harris County courthouse with a growing number of people calling for the arrests of Chauna and Terry.
"Johnny was such a great person. He was a generous person and he didn't deserve what happened to him," Melissa Hernandez, the victim's cousin, said.
The district attorney's office presented its findings to the grand jury, which met Thursday morning.
"We want justice for John Hernandez, and we want justice for the Thompsons as well. We want it for everybody involved in this case that this process be seen as fair and transparent," said Tom Berg, with the D.A.'s office.
Meanwhile, the office is asking anyone with evidence in the case to come forward. They are looking for more eyewitnesses and videos of the incident.