A Calif. Scientist Claimed He Could Cure HIV. But He Was Hiding a Dark Secret, and Plotted the Murder of Vermont Man

A biomedical researcher who claimed he had a cure for HIV has been convicted of plotting the 2018 murder of a man he feared would expose him. 

Serhat Gumrukcu, 42, hired Jerry Banks through two associates to murder Gregory Davis in 2018, in Vermont, U.S. Attorney’s Office, District of Vermont said in a statement last week.

Banks pleaded guilty to murder-for-hire, conspiracy to kidnap and money laundering in June 2023, per VT Digger.

Gumrukcu had claimed to have discovered a cure for HIV, which became the basis of a “multi-million-dollar biotech merger” with Davis, the Attorney’s Office statement said. 

Davis had threatened legal action against Gumrukcu over the biomedical engineer’s “role in a failed oil commodities transaction,” the statement said. The exact nature of the transaction was not clear in the statement, but Gumrukcu has also been convicted of wire fraud for that case.  

Fearing his fraudulent activities would be exposed, Gumrukcu contacted his friend, who then worked with an intermediary to recruit Banks for the murder, per the statement. 

On Jan. 6, 2018, Banks showed up at Davis’ Danville, Vt., home posing as a Deputy U.S. Marshal and abducted the father of six, the attorney’s office said in their statement. The following day, Davis’ body was found on a snowbank in the vicinity of his home. 

Banks said he had been hired by a man who went by the name “Turkish Prince” — a self-proclaimed title that prosecutors say Gumrukcu gave himself, NBC 5 reported. 

Investigators eventually tracked down Gumrukcu via emails and messages between him and Davis that showed tensions simmering between the two. 

Gumrukcu was interviewed twice by the FBI, but lied on both occasions, according to the statement. 

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Investigators went through banking information, emails and messages to track the four people involved in the plot. 

“Serhat Gumrukcu is a ruthless criminal whose greed drove him to order the death of his own business partner,” FBI Special Agent in Charge, Craig L. Tremarol said in response to the guilty verdict. “Today, our thoughts are with Gregory Davis’s family.”