After almost three years, Ramsey County prosecutors say they've reached the final phase of a sweeping investigation into four decades of criminal cases involving Michael McGee, the former medical examiner whose questionable methods have led to several wrongful convictions.

Ramsey County Attorney John Choi announced in a news conference Wednesday that his office has narrowed the review from more than 200 total convictions to seven murder cases in which McGee played a significant role in securing a verdict.

Choi said the legal team investigating McGee's record has reached the limit of its expertise. His office will now convene a panel of independent medical experts to determine whether McGee used sound science in those seven cases, he said, emphasizing that no wrongdoing has so far been proven.

"We have not made any final conclusion at all," Choi said. "We believe we need to have further review by medical experts on these particular cases to understand the significance and the impact of those seven cases."

Choi did not identify the cases under review, saying he didn't want to prematurely retraumatize families of victims or provide false hope to someone in prison. The review is expected to cost more than $500,000, Choi said, and he is committed to accepting the final recommendations "without fear or favor."

"Our top priority in this review is to create transparency and justice in the system," said Carrie Sperling of the Minnesota Attorney General's Office Conviction Review Unit, which is also reviewing some of McGee's cases. "Not one goal of our criminal justice system is met when we convict the wrong person of the wrong thing."

McGee has come under scrutiny in recent years following several independent reports and judges' opinions calling into question the science he used over his career.

At least four people have either been released from prison or resentenced to a lower penalty after revelations that McGee provided flawed or inaccurate testimony leading to their convictions, according to court records. This includes Thomas Rhodes, a Minnesota man who spent 25 years in prison based on "medically unsupported science," according to the results of a Minnesota Attorney General's Office investigation published last year.

"McGee reasoned backward — from the nonmedical evidence to the medical findings," the report said.

Since Rhodes' release from prison, he has filed a lawsuit accusing McGee of fabricating medical conclusions and providing false testimony in the 1996 drowning death of his wife.

Attorneys representing McGee did not reply to requests for comment for this and other recent Star Tribune stories examining questions over his record.

Long career now in question

McGee, once renowned for his ability to use emerging science to solve cases that stumped his colleagues, was the medical examiner in Ramsey County from 1985 to 2019. He worked in the county office as a forensic pathologist until he retired in 2021. He also served as a medical examiner for Washington County and more than a dozen other counties.

Choi's office has been investigating, with help from the New York-based Prosecutors' Center for Excellence, since 2021 after an appeals judge called McGee's testimony in the case of Dru Sjodin, a college student kidnapped and killed in 2003, "so unmoored from a scientific basis that it should not have been received at all."

"The evidence in the record demonstrates that McGee did much more than merely follow where the evidence and science led him," 8th U.S. Circuit Court of Appeals Judge Ralph R. Erickson wrote in 2021, in reversing the death penalty for Alfonso Rodriguez Jr. "Instead, he chose to play the role of a super sleuth, something akin to Sherlock Holmes."

Jim Mayer, legal director of the Great North Innocence Project, a nonprofit that seeks to reverse wrongful convictions in Minnesota, applauded Choi for pursuing a systematic review of McGee's past cases.

"They talk about where there's smoke there's fire. This is a case where we are beyond the smoke phase," said Mayer, whose organization is assisting in the review. "We have seen the fire, which is why we're all standing up here. The question is how far the fire has spread, what additional damage might be out there and how do we mitigate that harm."

Choi said the team has spent the past three years narrowing the list to cases in which verdicts were largely based on McGee's autopsy or expert testimony. Asked for his opinion on McGee's motives, Choi said it's not time for speculating.

"We need to do some work and let the facts and truth lead the way," he said.

Star Tribune staff writer Greta Kaul contributed to this story.