The brother of a Martha’s Vineyard artist was sentenced to 16 years in a Russian prison early Monday on espionage charges, the family has confirmed.

Paul Whelan, a former U.S. Marine who is the brother of Chappaquiddick resident Elizabeth Whelan, was arrested nearly 18 months ago while visiting Russia for a wedding, according to his family. While there, he was allegedly handed a flash drive that Russian officials have claimed contained state secrets and other confidential information.

The arrest has strained Russian-American relations and thrust Ms. Whelan from a quiet life on Chappy into the throes of a global power struggle. American officials, and the Whelan family, have suggested that the Russians want to use Mr. Whelan as a bargaining chip in a prisoner swap.

Ms. Whelan thanked the many Vineyarders who haven sent letters to Paul Whelan. — Jeanna Shepard

Since her brother’s arrest, Ms. Whelan and two other siblings have been working tirelessly with American government officials in Washington to secure Mr. Whelan’s release. The family has been adamant that their brother was wrongly detained and is not an American spy.

Mr. Whelan’s conviction and sentencing on Monday morning includes hard labor at a Russian prison colony. The 16-year sentence was two years less than the amount of time requested by the prosecution, according to an email from brother David Whelan.

“It was a bit of a shock of course,” Ms. Whelan said Monday, speaking to the Gazette by phone. “But we knew that the Russian Federation was not holding Paul for this long, only to let him go today. It was just a matter of what number they would say, and they said something astronomical, which was expected.”

“Now, hopefully, this means we can turn towards finding some resolution to this situation,” she said.

Before the pandemic hit, Ms. Whelan had pretty much moved to Washington in an attempt to lobby American government officials to advocate for her brother’s release. She was forced to come home in March due to the Covid outbreak, she said, adding that her brother has only had two phone calls from home in the time since.

Mr. Whelan’s lawyers plan to appeal the conviction, according to the statement from David Whelan — although Mr. Whelan said overturning the conviction would be unlikely considering the Russian judicial system.

“The court’s decision merely completes the final piece of this broken judicial process. We had hoped that the court might show some independence but, in the end, Russian judges are political, not legal, entities,” he wrote.

Efforts from American government officials have recently ramped up to secure Mr. Whelan’s release. Russian ambassador John Sullivan, Secretary of State Mike Pompeo and Rep. Bill Keating are among those advocating for his release.

Ms. Whelan said she was hopeful that the conviction would allow the governments to more easily broker a deal to get her brother home. She said the family had known for months that the conviction was a given and that the Russians have said they would not negotiate until Mr. Whelan was sentenced, meaning the unfortunate news on Monday could potentially serve as an opening for talks.

“What we have right now is we have a great deal of support from the State Department for getting this resolved,” Ms. Whelan said. “What we don’t have yet is that same signaling coming from the Russian Federation.”

Mr. Whelan underwent an emergency medical procedure for a hernia at the end of May, Ms. Whelan said, and fears for his health are serious.

The last American to be detained in Russia was Edmund Pope nearly 20 years ago. Mr. Pope, who was also held at Lefortovo prison, was eventually released after being sentenced to 20 years in a labor camp for espionage charges.

Ms. Whelan thanked Vineyarders for sending letters of support to her brother, and advocated for their continued transmittal. His address is listed on a Facebook page for Mr. Whelan.

“It has obviously been very, very good for his morale to have this kind of communication,” Ms. Whelan said. “The embassy likes to be able to be able to walk into the prison with a pile of mail, showing the Russians that nobody has forgotten about Paul, or about the injustice that is going on.”