By Kara Berg, The Detroit News
TROY, Mich. — A Troy judge is expected to announce Tuesday if the owner and three employees of a local medical facility, where a 5-year-old boy died last year in a hyperbaric oxygen chamber explosion, should stand trial on second-degree murder and involuntary manslaughter charges.
Thomas Cooper of Royal Oak underwent dozens of hyperbaric oxygen treatments at the Oxford Center in Troy for ADHD and sleep apnea. During a treatment on Jan. 31, 2025, a fire sparked in the chamber, killing Thomas.
The Michigan Attorney General’s Office has charged owner Tamela Peterson, safety director Jeffrey Mosteller and operations manager Gary Marken with second-degree murder and involuntary manslaughter. Aleta Moffitt, the hyperbaric chamber’s operator, is charged with involuntary manslaughter and knowingly placing false information in a medical record.
Assistant Attorney General Chris Kessel argued Oxford Center ignored safety protocols for hyperbaric oxygen chambers, specifically not using grounding straps. Grounding straps are wrist straps that connect a patient to the chamber to drain static electricity that may build up.
Prosecutors have alleged that the Oxford Center’s owner and the others charged ignored guidance from the chamber manufacturer’s manual, the National Fire Protection Association and the Oxford Center’s own training materials about safety in hyperbaric chambers. They contend the four workers are criminally culpable in Thomas’s death.
A ruling from 52-4 District Court Judge Maureen McGinnis is expected months after a preliminary examination for Peterson and the three Oxford Center employees started in September and included multiple witnesses, including some former employees.
Hyperbaric expert Francois Burman testified Sept. 16 that Thomas’s knee may have touched the mattress in the chamber, possibly causing static electricity to build up and lead to the spark that started the fire.
“Did they know the rules? Did they now the consequences for not following the rules? And did they ignore them both? The answer is yes,” Kessel said Jan. 20.
Kessel and the four defense attorneys made their closing arguments to McGinnis Jan. 20 at the last day of the preliminary examination. A preliminary exam determines if there is enough evidence to determine if there is probable cause to send a case to trial.
Moffitt’s attorney, Ellen Michaels, contended Moffitt was never trained to use grounding straps on patients, nor did she have any knowledge of them or read the chamber manufacturer’s manual. Michaels suggested Moffitt was caught up in the attorney general’s office determination to assign blame for Thomas’ death.
“An accident occurred. Someone had to pay,” said Michaels. “Public opinion said someone had to pay. The Attorney General said someone had to pay. So in a very short amount of time, four people were charged.”
Marken’s attorney, Todd Flood, meanwhile, said Marken did not have anything to do with decisions about patients or operating the chambers. He characterized his client’s role at the Oxford Center as one akin to a handyman.
Thomas Cranmer, Peterson’s attorney, said Peterson has been charged because of her status as the Oxford Center’s CEO, rather than because of any evidence she bears culpability for Thomas’ death. Cranmer referenced testimony from Troy Deputy Fire Chief Shawn Hugg, who said the investigation into the fire’s cause has not ended and there is no evidence that confirms the fire resulted from static electricity.
Peterson is charged in a separate case in the 53rd District Court in Howell with nine counts of health care fraud.
Thomas’s family has also filed a separate $100 million civil lawsuit against the Oxford Center, its owner and three employees as well as the chamber’s manufacturer for the little boy’s death.
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