A half-inch piece of metal lodged in the shoulder of Oregon refuge occupier Ryan Bundy could become central to the federal government's prosecution of an FBI agent accused of lying about firing two shots as police tried to arrest the 2016 takeover's leaders.

When Bundy was arrested along U.S. 395, emergency medics found him bleeding and wrapped his wound in a dressing.

He was taken to Harney District Hospital, where an X-ray revealed a metal fragment next to his right shoulder bone, presumably from a gunshot.

"There's a bullet in there," Ryan Bundy told The Oregonian/OregonLive. "I can see what it is. It's shaped like a bullet."

Bundy was in the back passenger seat on Jan. 26, 2016, as occupation spokesman Robert "LaVoy" Finicum swerved his pickup into a snowbank to avoid hitting a roadblock on the highway after driving off from a police stop. Oregon State Police and the FBI had moved in to arrest the key figures in the armed takeover of the Malheur National Wildlife Refuge as they drove off the federal bird sanctuary.

W. Joseph Astarita, a member of the FBI's Hostage Rescue Team, is accused of lying to FBI supervisors and Oregon detectives about firing two shots at Finicum's truck. One hit the roof of the pickup and another apparently missed altogether, investigators said.

They haven't found any casings or bullets tied to Astarita's rifle, so the suspected bullet in Bundy's shoulder could prove crucial.

The U.S. Attorney's Office also has copies of the X-ray and a federal prosecutor said in court last August that talks were underway with Bundy's lawyer to recover the object so government experts could analyze it as potential evidence in the case.

But Bundy, who represented himself at trial in both the Oregon occupation case and the 2014 standoff in Nevada near his father's ranch, said prosecutors need to deal directly with him. He said he has no lawyer representing him.

"If they want it, they can buy it from me," he said. "I might work with them."

If the metal is removed, forensic experts likely would be able to determine whether it's from Astarita's rifle.

That's because each time a bullet is fired through the barrel of a gun, it becomes imprinted with grooves and microscopic imperfections, markings specific to a particular gun, said forensic consultant Ronald Scott, retired commanding officer of the ballistics lab for Massachusetts State Police.

Investigators would fire the same caliber bullet from the agent's rifle and compare the markings on it to the markings on the object recovered from Bundy.

Prosecutors could get a search warrant to extract the suspected slug, though it would be unnecessary if Bundy agreed to undergo surgery to remove it. Bundy hasn't agreed so far. He didn't say how much money he would want for the fragment.

"Either way, I would expect the government to pay for the surgery and to do so carefully in a way that preserves the evidence," said Christopher T. Robertson, associate dean and health law expert at the University of Arizona's law school.

"If the U.S. Attorney's Office or FBI want it that bad," Scott said, "one or the other agency would likely come up with the funds."

Bundy, who was crouched down in the back seat as Fincum's truck veered into the snowbank, said he felt the shot after the truck had stopped and as Finicum was stepping out of the pickup.

Moments later, state troopers fired three shots that struck Finicum, killing him as police said he reached inside his jacket. He was carrying a loaded 9mm pistol in an inner pocket, authorities said. State police also had fired three times at Finicum's truck as it sped toward the roadblock, investigators said.

Bundy said his right shoulder sometimes still hurts. When treated at Harney District Hospital in Burns, doctors suggested a plastic surgeon at Oregon Health & Science University in Portland could do the removal but Bundy declined.

Astarita's defense lawyers have asked the court to dismiss the case against the FBI agent, arguing that the charges solely rest on a computerized animation of the suspected shooting that they contend is "junk science" instead of any witnesses, evidence or ballistics. Astarita has pleaded not guilty to three counts of making a false statement and two counts of obstruction of justice. Astarita's local defense lawyer, David Angeli, declined any comment about the metal fragment in Bundy's shoulder.

If Bundy consents to have the metal removed, special procedures for the handling of the fragment - from the moment of removal to its packaging and review by a forensic lab -- would be required, forensic experts say.

An assistant U.S. attorney and an FBI investigating agent likely would be at the hospital but not allowed in the operating room during the surgery, Scott said. The surgeon would be instructed not to damage the fragment, he said.

"You can't be grabbing it with pliers or metal forceps," Scott said. "You want to keep that bullet in as good a condition as possible."

The doctor would be asked to use plastic- or rubber-tipped forceps. Once removed, an investigator or prosecutor would photograph the evidence before it's placed into a plastic cup or jar, and the investigating agency would take custody of it, Scott said.

"There's no question that removal of the bullet is mandatory in order to make an identification," he said. "If I was working for the FBI, I wouldn't be sending it in the mail but hand-carrying it on a plane to the FBI lab so it wouldn't get lost."

There's the possibility that the metal fragment or bullet traveled through window glass or the truck's sheet metal before entering Bundy's shoulder, which could have altered its characteristics. But a forensic expert still could examine and compare the characteristics from the fragment to a bullet fired by the agent's rifle, Scott said.

If Bundy wants to use the fragment as evidence to help Finicum's wife, Jeanette Finicum, in her expected lawsuit against Oregon State Police and the FBI, her lawyer could send a letter to the agency that takes custody of the fragment requesting that the evidence be preserved.

No suit has been filed yet, and attorney Brian Claypool, who has spoken on behalf of Jeanette Finicum and her family in the past, said Tuesday he's no longer representing the family.

Some medical ethical issues might also come into play. A doctor would have to determine that there's not a high risk for any complications to surgically remove the object from Bundy's shoulder.

"The government cannot force a surgeon to do the work but would have to contract with one to do so for a fee," Robertson said.

-- Maxine Bernstein

mbernstein@oregonian.com

503-221-8212

@maxoregonian