The charge stems from Jaquaree Simmons' death back in 2021, but it also comes on the heels of an Eyewitness News investigation revealing a record-breaking number of inmate deaths at the jail last year.
SEE MORE: 13 Investigates: Decade-high inmate deaths just one concern at Harris Co. jail
Court documents showed Eric Morales caused the injuries that killed Simmons, but it took two years and multiple grand jury proceedings to get an indictment for manslaughter.
"It's a culmination of all the evidence we had and testimony from witnesses," Assistant District Attorney Kimberly Clark said after revealing how she built the case against Morales.
None of the 1,490 cameras inside the jail at the time captured video of the confrontation that led to Simmons' death, but the sheriff's office alone completed 73 interviews.
"Yes. I believe there's a criminal- crimes committed in this whole transaction," Harris County Sheriff Ed Gonzales said after a three-month investigation back in 2021.
SEE MORE: 11 Harris County Sheriff's Office employees fired after inmate's death; 6 suspended
He also announced he was firing 11 detention officers who violated policy and possibly the law. Morales is the only one charged.
"It took us a while just to get to this point. While I'm hopeful, I do not expect additional charges," Clark added.
Court documents show Morales caused Simmons' death by dropping him on his head, kneeing him in the head, striking his head against the door, and striking his head against the wall.
ABC13 also spoke with his mother, LaRhonda Biggles, who told us two years ago that she knew he was hurting and confused when the alleged assault happened.
"They broke a family horribly. They didn't have to kill my child like that, and I'm not going to stop until justice is served for my baby," Biggles said.
Simmons' was incarcerated for allegedly possessing a weapon as a felon, but she said he did not deserve to die for what he did. That message was echoed by the district attorney's office, as four more incarcerated people have died at the Harris County Jail just this year.
"The message that's being sent is that we prosecute regardless of which side of the bars you're on," Clark said. "We're seeking justice. If it occurred and it was a crime, we are going to investigate and pursue it to the fullest extent of the law."
Late Monday, Senior Deputy Thomas Gilliland of the Harris County Sheriff's Office offered a response in light of the charge:
Nearly two years have passed since Jaquaree Simmons died from injuries he suffered while in the Harris County Jail. The Harris County Sheriff's Office immediately conducted a thorough internal investigation that revealed significant policy violations. Based on these findings, Sheriff Ed Gonzalez accepted his Administrative Disciplinary Committee's recommendation to terminate 11 employees and suspend 6 other employees in May 2021, and publicly expressed his sympathy to Simmons' family for the loss of their loved one.
The Houston Police Department conducted a separate criminal investigation into the events surrounding Simmons' death. The Harris County District Attorney's Office recently presented the results of the HPD investigation to a grand jury, which issued an indictment against Eric Morales, a former detention officer, alleging he committed the crime of manslaughter. Morales was among the 11 employees fired as a result of the Sheriff's Office internal investigation.
In June 2021, the Sheriff's Office implemented Active Bystandership for Law Enforcement (ABLE) and Integrating Communication and Tactics (ICAT) into the training program for all detention officers. So far, 1,164 detention officers have completed the training.
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