SALEM, Mass. (AP) — A former Massachusetts Institute of Technology professor who once staged his own shooting has been found guilty of forgery and other charges for trying to swindle millions of dollars from his dead son’s estate.

John Donovan Sr., 80, of Hamilton, was convicted Tuesday by a Salem Superior Court jury after a monthlong trial and four hours of deliberations, according to a statement from the office of Essex District Attorney Jonathan Blodgett.

Donovan forged 25 documents, including will codicils, deeds, land transfers, mortgages and releases of judgments against him at the county registry of deeds in December 2016, prosecutors said. His youngest son, John Donovan Jr., died in April 2015 at age 43 after being diagnosed with cancer.

The elder Donovan and his children are estranged and according to witness testimony, the son did not want his father to have anything to do with his family, prosecutors said.

The forged documents would have given the older Donovan land worth $5 million from his late son’s estate, prosecutors said.

“The general public relies upon the integrity of documents filed with the Registry of Deeds,” Blodgett said in a statement. “Thanks to the diligence and professionalism of the staff at the registry, who raised concerns about the documents filed by Mr. Donovan, this fraudulent scheme failed.”

Sentencing was scheduled for May 16.

The senior Donovan was a wealthy businessperson who made a name for himself as a technology guru, starting more than a dozen companies and publishing books. He taught business at MIT from 1969 to 1997.

Tuesday’s conviction was not his first brush with the law.

He was found guilty in 2007 of staging his own shooting outside his business office in Cambridge in December 2005. He said he was attacked by two Russian hitmen hired by another son.

But prosecutors at the time said he shot himself in the abdomen and fabricated the story to frame the son in an effort to gain the upper hand in a legal battle over control of millions of dollars worth of trusts. He was convicted of filing a false police report and was sentenced to two years of probation.

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