Fake U.S. Marshal, Real Murder: The Chilling Case of Dr. Serhat Gumrukcu

What started as a business deal gone wrong ended in a deadly plot that sounds more like a movie script than real life.

In a Vermont courtroom this week, Dr. Serhat Gumrukcu — a California-based medical researcher with dreams of biotech fame — was found guilty of masterminding the murder of his business associate, Gregory Davis. The 2018 killing was carried out by a man pretending to be a U.S. Marshal, and prosecutors say it all traces back to Gumrukcu’s desperate attempt to silence Davis before he could blow the whistle on a shady oil deal.

A Murder Staged to Look Like a Federal Arrest

On a snowy January evening in 2018, 49-year-old Gregory Davis was taken from his home in Danville, Vermont, by a man dressed as a U.S. Marshal. His wife and children watched in confusion and fear as Davis was handcuffed and led away, seemingly under arrest.

What they didn’t know at the time was that the man in uniform, Jerry Banks, wasn’t a law enforcement officer at all — just someone hired to carry out a murder.

Davis’s body was found the next day along a backroad about 15 miles away. He had been shot multiple times and left in a snowbank. Investigators were baffled at first, but the trail eventually led to a shocking suspect: Dr. Serhat Gumrukcu.

From Medicine to Murder

Gumrukcu, originally from Turkey, had been building a name for himself in the biotech world. He wasn’t licensed to practice medicine in the U.S., but he presented himself as a scientist, an innovator — and, as one witness put it, a man who called himself the “Turkish Prince.”

Behind the scenes, though, things weren’t so polished. Gumrukcu had been involved in a multimillion-dollar oil investment deal with Davis that fell apart. Davis, feeling scammed, was threatening legal action and planned to expose Gumrukcu’s alleged fraud.

With his reputation — and potentially his future at Enochian Biosciences, a biotech company he co-founded — on the line, prosecutors said Gumrukcu made a deadly decision: have Davis killed.

A Murder-For-Hire Plot Unravels

Gumrukcu didn’t act alone. He tapped an associate, Berk Eratay, to help find someone who could “take care of” Davis. Eratay reached out to a former neighbor, who then contacted Jerry Banks, a former jail guard in Colorado with a dark past and the means to carry out the job.

Banks traveled cross-country, posed as a federal agent, and carried out the killing in cold blood. He later pleaded guilty to his role, as did Eratay and the others involved in arranging the hit. All three men eventually turned on Gumrukcu and testified against him in court.

The Trial: Lies, Greed, and a Stunning Fall

During the trial, prosecutors painted a clear picture of premeditation. They presented evidence showing how Gumrukcu stood to lose millions if Davis followed through with his legal threats. Witnesses testified that Gumrukcu practiced medicine without a license, lied to the FBI, and built much of his image on deception.

In a last-ditch effort to win over the jury, Gumrukcu’s defense team tried to portray him as a compassionate healer — someone whose life was about saving others, not hurting them. But it wasn’t enough.

After hours of deliberation, the jury returned a guilty verdict on charges of murder-for-hire and conspiracy.

A Family Torn Apart

For Davis’s loved ones, the verdict brings some closure but no true relief. He left behind a pregnant wife and six children who are still grieving the loss of a husband and father taken from them in the most senseless way.

“This was someone Greg trusted, someone he went into business with,” said a close family friend. “And that trust cost him his life.”

What Comes Next

Gumrukcu now awaits sentencing and could face life in prison. The others involved in the plot are also expected to receive lengthy sentences, though their cooperation with authorities could play a role in the final decisions.

Enochian Biosciences has publicly distanced itself from Gumrukcu and emphasized he no longer has ties to the company.

While the court case may be over, the fallout from this shocking crime will linger — in the biotech world, in the business community, and most of all, in the hearts of those who knew Gregory Davis.