An autopsy was scheduled for Wednesday on 62-year-old Dennis Lashley who was found dead at the medium-security prison in Springfield Tuesday.
The South Dakota Department of Corrections says Lashley died after getting into a fight with another inmate, 49-year-old Kendall Osteen.
Osteen has not been charged with a crime but an investigation is underway.
It's the third time this year a DOC inmate is linked to a homicide investigation.
Earlier this year, Eric Robert, Rodney Berget and Michael Nordman were charged with the death of Corrections Officer Ron Johnson.
In July, James McVay was charged with murder after walking away from a transitional housing program and killing 75-year-old Maybelle Schein.
It's the job of the nine-member South Dakota Corrections Commission and its chairman, state Senator Craig Tieszen of Rapid City, to investigate these incidents closely.
"It's not our job to run the prison but it's our job to make sure the prison properly reviews incidents like this. That they take corrective measures when necessary. That they do all the right things to make sure all the policies are in place," Tieszen said.
The commission is expecting a report on the Springfield case Thursday at its regular meeting. It's similar to the briefings they've heard on the other cases this year.
Tieszen says he's been satisfied with the response from officials in the Department of Corrections who have looked at what went wrong and have made improvements in the prison, like adding more corrections officers in certain areas, adding more cameras and asking for outside groups to look at the operations.
Tieszen believes the prison system is safer now than it was earlier this year.
"Obviously, we've now had another incident. We'll need to continue to take a look at that, but generally, yes, I've been satisfied with the reaction. That's the way professional corrections officials should operate is that they should be willing to review all the circumstances and make changes when they feel it's appropriate," Tieszen said.
And even though there have been three major incidents this year, Tieszen believes the public should have confidence in the way the Department of Corrections is being operated.
"At this point, I think so. I believe generally that we have a good corrections system and that we have good corrections employees. Again, that's all subject to constant review and we'll continue to do that," Tieszen said.
The corrections commission is scheduled to meet Thursday morning at the penitentiary.
They not only expect to hear a report on the Springfield incident but are scheduled to take a closer look at the review done by the National Institute of Corrections following the death of Ron Johnson.