A Twin Cities cybersecurity and computer forensics expert who has assisted in numerous police investigations is facing scrutiny amid allegations that he misrepresented his education and employment history.

The Hennepin County Attorney’s Office confirmed on Friday it has opened an investigation into Mark Lanterman, chief technology officer for Minneapolis-based firm Computer Forensic Services (CFS).

In his role at CFS, Lanterman routinely lent his expertise to police investigations and testified in more than 2,000 cases across the country. Now, the attorney’s office is looking into how his involvement could impact cases both past and present.

The Hennepin County Attorney’s Office said a member of the Wisconsin Bar approached them with concerns that Lanterman had not accurately represented his qualifications.

“At this time, the Hennepin County Attorney’s Office has been unable to fully verify Mr. Lanterman’s educational and employment background, and the office will not rely on his work or testimony in pending cases,” the office said.

In response, Lanterman issued a video statement saying he was “deeply disappointed” in the allegations against him and stood by his stated qualifications.

“My work and background have been scrutinized countless times in an adversarial setting,” Lanterman said. “It is the nature of the work that I and the company do. I stand by the truth of my background and credentials.”

While the Hennepin County Attorney’s Office says it does not contract with Lanterman, it has so far sent nine disclosures on cases that could have been impacted by his work with law enforcement.

“Our office is engaged in an ongoing review to determine the total number of cases affected and will continue to send disclosures as appropriate,” the attorney’s office said.

‘Unchallenged until now’

Lanterman’s profile on the CFS website says he “completed his postgrad studies in cybersecurity at Harvard University” and is certified by the U.S. Department of Homeland Security as a Seized Computer Evidence Recovery Specialist. He also says he worked on the U.S. Secret Service Electronic Crimes Taskforce before entering the private sector.

Sean Harrington — the whistleblower who raised concerns about Lanterman’s past — issued notices to several lawyers, courts and clients connected to CFS, including attorneys on a civil case in New Jersey federal court.

The defense attorneys on that case sought to have the judge throw out Lanterman’s testimony in light of a claim that he only completed a certification program through Harvard Online and did not earn a postgraduate degree from the Ivy League university.

“What Mr. Lanterman took was a single ‘Online short course’ administered through GetSmarter in April of 2018. The program awarded a digital certificate, is worth no college credit, and there are no undergraduate prerequisites,” a letter from attorneys Michael Warshaw and Edward Miller states.

In response, Lanterman disparaged Harrington and his motives.

He pointed out that Harrington’s company, Prescott, Wisconsin-based Adamant Digital Forensics, is a direct competitor to CFS. Lanterman also alleged Harrington had a history of mental illness, as documented in a 2007 court filing, and that he has “feared for his family’s safety because of Mr. Harrington’s obsession with me.”

Lanterman also addressed the difficulty in acquiring his undergraduate transcripts from Upsala College in New Jersey. The liberal arts college went bankrupt in 1995, and Lanterman says those academic records are now kept at Felician University, which he claimed “could not locate my transcripts or diploma … possibly due to unresolved money-related issues.”

Warshaw and Miller weren’t convinced.

“It is respectfully suggested that such a statement does nothing to prove that his academic qualifications are as he claims them; it merely notes that they have gone unchallenged until now,” a letter addressing the court states.

Why credibility matters

5 EYEWITNESS NEWS asked defense attorney Charles Ramsay why people giving expert testimony need to be carefully vetted. He says if questions are later raised about that person’s background and credibility, it could throw the entire case in doubt.

“The cases ongoing — they will find a new expert,” Ramsay said. “The problem really lies in cases that have been resolved, where there have been convictions.”

Credibility concerns can lead to lengthy reviews and change the outcomes of some cases, Ramsay says.

“If, however, there’s a trial and that expert’s testimony was a central or focal point of the case, and that it helped determine the person’s guilt, then a case like that or in facts like that, any conviction should be overturned,” Ramsay said.

One current review in Ramsey County involving former Medical Examiner Dr. Michael McGee’s credibility has been ongoing since 2021.

At one point, more than 200 Ramsey County cases linked to McGee were flagged for closer examination. That number has since been narrowed down to seven murder cases.

It’s unclear how long Hennepin County’s review will take and if any other counties are taking similar action.