By DAMIEN FISHER, InDepthNH.org
CONCORD — Deputy Chief Medical Examiner Dr. Mitchell Weinberg’s testimony on Wednesday did not exactly shore up the state’s second-degree murder case against former Corrections Officer Matthew Millar in the death of Jason Rothe.
During his day on the witness stand in Merrimack County Superior Court, Weinberg Wednesday conceded that his opinion that State Prison for Men Secure Psychiatric Unit patient Jason Rothe died because Millar put his knee on Rothe’s back isn’t the only way to interpret the medical evidence gathered in the autopsy.
“I wish I had better information,” Weinberg said.
Under cross-examination, Weinberg said that he used the reports and videos gathered by New Hampshire State Police investigators to help reach his conclusion that Rothe’s death was a homicide caused by traumatic compressional and positional asphyxiation.
The key witness in the investigation was Lesley-Ann Cosgro, who has since retracted her most damning accusation. Cosgro originally told investigators in 2023 that she saw Millar press his knee into Rothe’s back for up to several minutes. But when she testified this week, Cosgro said she saw Millar’s knee on Rothe’s back for “seconds, flashes of seconds.”
“My reaction to that is I don’t know what that means,” Weinberg said.
Weinberg tried to point to another witness statement he used to come to the conclusion Millar put his knee on Rothe’s back for an extended period. Using his own copy of his autopsy report, Weinberg pointed out Millar’s own statement that he used his knee, placed on the ground, to get leverage during the struggle with Rothe.
Millar was arrested in February of 2024, almost a year after Rothe, 50, died during a violent incident inside a SPU dayroom. At the time, police accused Millar of putting his knee into Rothe’s back for several minutes as Rothe was handcuffed and not moving. The accusation is based on Cosgro’s statement, and backed up by Weinberg’s autopsy.
But so far, none of the witnesses prosecutors have called testified Millar kneed Rothe for an extended period of time. That includes Cosgro. In fact, of the five original witnesses to the April 29, 2023 incident, Cosgro was the only one who ever told investigators she saw Millar knee Rothe while he was handcuffed.
It’s not unusual for medical examiners to use evidence from police as they interpret medical data in a suspicious death. In this case, Weinberg viewed a video State Police investigators made of Cosgro kneeling on a dummy to demonstrate her accusation against Millar.
The evidence that Weinberg cites for his conclusion that Rothe died from traumatic, compressional and positional asphyxiation, such as injuries to his back, the inside of his throat, and his eyes, could also be caused by other violent actions taken during the April 29, 2023 confrontation. When defense attorney Eric Raymond asked if Rothe’s back injuries could have been caused by Rothe’s own struggle against the officers, Weinberg conceded that they could.
“Yes, it seems plausible,” Weinberg said.
Weinberg could not say how long Millar’s knee would need to be on Rothe’s back to cause the back injuries he found in the autopsy. The video record does not include the eight to nine minutes when Millar allegedly used excessive force.
“I can’t say how many seconds. I don’t know how long pressure was applied to Mr. Rothe’s back. I would love to have known, that would have made my job exponentially easier,” Weinberg said.
The fact Cosgro recanted her original statement to police only became known to Weinberg about two weeks ago, he said. He’s not changed his opinion on Rothe’s death since, but he’s not been able to unlink his findings from Cosgro.
Cosgro was disciplined in April of 2024, after Millar was arrested, for her many failures leading the extraction team to get Rothe out of the dayroom. She was also cited by then-DOC Commissioner Helen Hanks for lying about Rothe’s death.
The fact that Cosgro was disciplined, and the fact that she recanted her original accusation, was hidden from prosecutors and defense lawyers as the DOC did not hand over all the evidence that was held in the case. More than 5,000 pages of evidence was finally revealed in March, weeks before the trial was originally set to start. The trial was set back to June to give both sides time to digest the new information, including the fact the DOC was essentially hiding exculpatory evidence in a murder case.
Weinberg will continue his testimony Thursday, and prosecutors have said they plan to call two more witnesses tomorrow if there’s time. The trial will take a break on Friday and resume again on Monday due to scheduling conflicts.