Paul Carter and his friend David Barnes have been speaking with each other since their days in first grade in Huntsville, Alabama, more than 60 years ago.

Yet since Jan. 13, 2022, their conversations over the phone haven’t been the same.

“It’s hard to sit there and hear him just plea, ‘Somebody get me home,'” Carter told ABC News in an interview.

Barnes, a 68-year-old father of two boys, is serving the longest prison sentence of any American who is currently being held in Russia. He was recently relocated to a penal colony hundreds of miles from Moscow.

Tuesday marks four years since Barnes was taken into custody.

His family says Barnes’ arrest came after he traveled from his apartment in The Woodlands, Texas, to Russia at the end of 2021 to try to gain visitation or custody rights to his sons through Moscow’s family court system.

Barnes’ ex-wife, Svetlana Koptyaeva, had taken their children to her native Russia following bitter divorce and child custody proceedings in Montgomery County, Texas. Upon learning of Barnes’ arrival in Russia, his family says she contacted law enforcement in Moscow and accused him of having abused the two boys.

“[She] did not want him to have access to his children, so she made the worst possible accusation that she could come up with,” Margaret Aaron, Barnes’ sister, told ABC News.

Moscow prosecutors’ case against Barnes was unlike any other involving an American jailed in Russia in recent memory, since Barnes was not accused of committing a crime on Russian soil.

Instead, Moscow prosecutors alleged that he abused his sons in suburban Houston, even though Texas law enforcement says they had no involvement in the Russian trial and previously found those allegations to not be credible after conducting their own investigation in response to Koptyaeva’s claims.

“I stand firmly by the allegations against Mr. Barnes,” Koptyaeva wrote to ABC News in an email Monday. “They are supported by my sons’ testimonies and evidence presented in both U.S. and Russian courts.”

Barnes was convicted by a judge in Moscow in 2024 and sentenced to more than 21 years in prison.

“Was it a fair trial? By no means,” Carter said.

After spending years in a detention center in the Russian capital, Barnes was recently transferred to the IK-17 penal colony, according to a spokesperson for his family. The facility previously housed other high-profile detainees like American Paul Whelan, who was freed from Russia in 2024 as part of a prisoner swap.

Carter and Barnes’ siblings have maintained their hope for years that an exchange like the ones involving Whelan, Brittney Griner or Trevor Reed could bring Barnes back.

“We can’t speak for the other people that are in jail in Russia but we absolutely know without a doubt that David is an innocent guy that’s being held on some horrendous charges,” Carter said.

‘Nothing to justify what happened’

While Barnes already stood trial in Moscow, prosecutors more than 6,000 miles away in Texas are hoping that his ex-wife will face a different set of accusations in a courtroom 40 miles north of Houston.

The criminal case against Koptyaeva dates back nearly seven years.

From 2014 to 2019, Texas court records show that Barnes and Koptyaeva were going through an acrimonious divorce and child custody dispute.

“It gradually deteriorated,” Carter said. “He married a woman that he loved and brought two children into the world and, through forces that he didn’t understand or see, it went downhill.”

Koptyaeva raised serious accusations against Barnes during this time, accusing him of abusing their children, which he vehemently denied.

“I can say that the allegations against Mr. Barnes were investigated and evaluated by law enforcement here in Montgomery County and charges were not brought against him,” Montgomery County First Assistant District Attorney Kelly Blackburn told ABC News on Monday.

The custody battle between Barnes and Koptyaeva ultimately resulted in a family law trial.

“A jury also heard evidence regarding the allegations during his custody dispute in the family law trial and even after hearing about the allegations, still awarded Mr. Barnes custody of his two children,” Blackburn said. “And that is when his ex-wife fled with them to Russia.”

The Montgomery County Sheriff’s Office alleged that despite a judgment giving Barnes partial custody of their children, Koptyaeva “failed to comply with any condition for travel outside of the United States with the children,” and left the country with the boys on a Turkish Airlines flight from Houston to Istanbul on March 26, 2019.

Interpol published yellow global police notices containing pictures of the children and Koptyaeva was subsequently charged with interference with child custody, a felony crime in Texas.

A warrant for Koptyaeva’s arrest in connection with this charge is still active, according to Blackburn.

“I am not planning to return to the United States,” Koptyaeva told ABC News. “However, if I were to do so, I would plead not guilty, as I did nothing wrong. My actions were solely to protect my children from severe abuse, something any parent would do in my situation.”

A Texas court subsequently designated Barnes as the primary guardian of the children, but since the boys were believed to have ultimately ended up in Russia with Koptyaeva, he was unable to have a relationship with them.

Barnes’ friends and family maintain that Barnes’ desire to legally reunite with his children is what prompted him to travel to Moscow after COVID-19 restrictions were lifted. Instead, he ended up in a series of Russian detention centers.

“There’s nothing to justify what happened,” Carter said.

New Year, new hope?

As Barnes begins his fifth year of detention in Russia, for the first time he is being held in a penal colony a long distance away from Moscow

“From what we understand, the climate is quite a bit different,” Carter said, explaining that while Barnes was often housed in a cell with 14 to 17 other people in Moscow, he has more room to walk around in his new facility.

Carter said that the penal colony is a labor camp of sorts, but Barnes’ labor has largely been restricted to shoveling show. He is worried about his friend’s medical condition though, noting that Barnes has lost around 10 teeth since he has been in custody.

Koptyaeva has maintained that Barnes was justifiably charged and convicted, while Barnes’ relatives and acquaintances have been advocating for the U.S. government to declare that Russia is wrongfully detaining Barnes.

“We commend all efforts to secure Mr. Barnes’ release,” Rep. Dan Crenshaw, Rep. Dale Strong and Sen. John Cornyn wrote in a letter to Secretary of State Marco Rubio in November. “As the Administration continues negotiations with Russia, we urge you to utilize every tool available to facilitate his return to the United States.”

Blackburn, the Montgomery County First Assistant District Attorney, said he is not in a position at this time to say whether Barnes’ detention in Russia is wrongful, noting, “I don’t know what evidence was presented during the trial or anything else about how the proceeding[s] [were] conducted.”

The State Department has not answered ABC News’ questions over whether it considers Barnes’ detention to be wrongful.

“The Department of State has no higher priority than the safety and welfare of American citizens,” the agency said in a statement to ABC News. “U.S. Embassy officials continue to provide consular assistance to Mr. Barnes.”

Carter said that there has been increased advocacy against Barnes’ detention recently and that he is hopeful that the Trump administration will be able to bring his friend home — but fears Barnes being devastated if he is left out of another prisoner exchange.

“He’s been in some insufferable conditions and it doesn’t need to continue,” his friend said.

ABC News’ Tanya Stukalova contributed to this report.