OAKLAND COUNTY, Mich. – All four of the workers charged in the death of a 5-year-old boy who was killed in a hyperbaric chamber explosion at an Oakland County health care facility were back in court on Wednesday.
Tamela Peterson, 58, of Brighton, Jeffrey Mosteller, 64, of Clinton Township, Gary Marken, 65, of Spring Arbor, and Aleta Moffitt, 60, of Rochester Hills, virtually appeared before 52-4 District Court Judge Maureen McGinnis on Wednesday, April 30, for a probable cause conference.
You can watch the full hearing in the video at the top of this article.
The four workers were charged after Thomas Cooper was killed when the hyperbaric chamber he was receiving treatment in exploded at the Oxford Center in Troy on Jan. 31, 2025. His mother was also injured.
Read more -- Deep dive into allegations against 4 Oakland County workers in 5-year-old’s hyperbaric chamber death
The attorneys for each defendant agreed that an inspection was necessary before a preliminary examination could be held. There is a temporary restraining order for the Oxford Center in Troy and its contents, including the chamber where the explosion happened, which is keeping the parties from entering the location.
The delay is partly happening because the civil attorneys need to agree on a set of protocols for the inspection, according to Alona Sharon, Mosteller’s defense attorney.
Assistant Attorney General Chris Kessel agreed that each attorney and their experts should be present for the inspection, and that this should happen before the preliminary examination.
He also said that if the civil attorneys keep delaying the inspection, then they should collectively go to Oakland County Circuit Judge Brennan to address this.
McGinnis agreed to wait on a preliminary examination and scheduled another probable cause conference for May 28.
After that, Marken and his attorney, Todd Flood, stayed to discuss a motion regarding his bond conditions with the judge.
McGinnis said that Flood claimed that Marken was ordered to home confinement with no exceptions, but that wasn’t the case. She said he can leave for medical appointments, employment and any court-related matters or meetings with his attorney, as long as he contacts pretrial services to verify them before he leaves his house.
Flood, who didn’t start representing Marken until after his arraignment, said he never received the pretrial release order, and that Marken told him that he was told he couldn’t even go to his mailbox.
“I was told I couldn’t even go to my mailbox because the distance was within 500 feet or so. She [pretrial services] was very specific that I was confined to home, and I would have to request to see my attorney or go to my doctor, and that was it. My original ask was to go to church, which is miles away.”
After McGinnis discussed the exceptions again, Flood asked if there could be a set period of time (such as 9 a.m. to 3 p.m.) for Marken to be able to leave his house.
Flood said that because he and Marken are 100 miles apart, Marken being able to leave would allow for them to have spontaneous meetings when certain things come up or if something on his schedule clears up. But the judge said that since they are so far apart, meetings should be scheduled in advance.
Marken told the McGinnis that being able to go to church was his biggest concern with this request.
Kessel said he wasn’t opposed to an exception for Marken to be able to go to church, and McGinnis said she would talk to pretrial services about this.
Marken also mentioned that he holds men’s bible studies on his farm on Tuesdays and Thursdays, but he isn’t even able to go to the farm, and also tend to the garden and chickens, because the distance is too far from the radius that he was told he had to stay within. He told the judge that there are two other families’ homes that are connected to his farm, which is at the center of their properties.
McGinnis said, due to the farm property being an unusual circumstance, she would need more information before deciding on that.
What charges are the four employees facing?
Peterson, the Oxford Center’s founder and CEO, along with Mosteller, the safety manager, and Marken, the primary management assistant, were charged with second-degree murder.
They were also given the alternative charge of involuntary manslaughter, which means that a jury will decide which charge accurately fits their conduct.
Moffitt, who was allegedly operating the hyperbaric chamber at the time of the explosion, was charged with involuntary manslaughter and falsifying medical records.
Previous court coverage for 4 employees
The last time all four of these workers were in court at the same time was on March 19 for probable cause conferences. During these, it was determined that another probable cause conference would need to be set due to the amount of discovery that needed to be reviewed in the case.
Mosteller and Peterson have appeared in court since their first probable cause conferences for hearings about their bond.
During a hearing on Wednesday, March 26, McGinnis lowered Mosteller’s bond from $250,000 to $50,000 cash/surety. She pointed to the fact that Mosteller had been given a court-appointed attorney and to information about his income and expenses that the court didn’t initially have.
Read more -- ‘Whatever gets bodies in chambers’: What police say Oxford Center CEO texted about hyperbaric treatments
The judge wouldn’t lower Peterson’s $2 million bond, though. During a hearing on April 4, 2025, the judge said that while the other defendants seem to be respecting the court process, Peterson hasn’t.
The CEO allegedly made phone calls from jail to her family members, who are also employed by the Oxford Center, and discussed the case, including where to move around documents and who to hire and fire at the center.
McGinnis said that if Peterson couldn’t follow orders while in jail, she wasn’t comfortable having her at home and denied her bond modification.
Despite that, Peterson still ended up posting her bond and was released from jail at 1 p.m. on April 9, 2025.
Marken, who was given a $250,000 bond, and Moffitt, who received a $100,000 bond, were released in early March.
Mosteller was released on March 31 after his bond was lowered.