Even as pot shops rake in millions in Colorado, and the possibility grows of the drug becoming legal in as many as a dozen other states, a handful of Americans are serving life sentences for selling marijuana.

At least 25 people have been condemned to live out their days behind bars because they were involved in the marijuana trade, according to The Human Solution, a pot advocacy group. Some played relatively small roles in larger distribution rings and got life sentences in part because they refused to plead guilty and testify against associates. Others held positions of power in major trafficking organizations.

James Romans, a divorced 42-year-old father of three from Indiana, says he belongs in the former category. But last year, a federal judge ruled differently, sentencing him to life based on evidence suggesting that he helped run a multimillion dollar operation.

Whatever his role, the case raises questions about the fairness of punishing marijuana offenders with the criminal justice system’s harshest penalty short of death.

“It doesn’t seem to me in this day and age, when states are debating whether marijuana should be legal, that people who traffic in it should be spending their lives behind bars,” said David Zlotnick, a former Assistant U.S. Attorney and an expert on drug sentencing laws at Roger Williams University School of Law in Rhode Island. “If we’re not sure whether this drug should even be an illegal narcotic, why are we sending people to jail for life for it?”

As Romans tells his story, he was working low-wage construction jobs in suburban Indianapolis in 2004, struggling to support his kids and “dibbling and dabbling” in pot dealing, when one of his childhood friends offered him a chance to join a big-time marijuana ring. Romans claims he worked as a middleman, relaying money from about 15 lower-level dealers to the friend, Eric Pieper, whom Romans now says was the boss.

“I knew there could always be consequences,” Romans said on the phone Tuesday night from McCreary federal prison in Kentucky. Still, he never imagined his role would lead to anything “major,” he said.

And it didn’t -- not at first. After police arrested him in a sting in 2010, a state court found him guilty of dealing 27 pounds of pot and ordered him to participate in a “work release” program in prison. During his year in the program, Romans was allowed to leave the prison each day to drive a delivery truck for a retail company that sold fur coats.

But with his release date only two weeks away, federal agents picked him up and flew him to a jail in Sherman, Texas, where he waited for a new trial to begin. Investigators said they had uncovered evidence that showed he had been dealing pot not by the pound, but by the ton. The feds had opened a new case, arguing he'd been a major player in a trafficking organization responsible for transporting more than 10,000 kilos of marijuana into the U.S. from Mexico.

Under the federal government’s sentencing guidelines, which the United States adopted in 1987 at the height of the country’s drug war, the sale of more than 10,000 kilos of marijuana qualifies as a very high-level offense. If a judge concludes that the defendant possessed guns “in furtherance” of the crime, operated a house where the drugs were stashed, or helped run a trafficking organization, the level of the offense goes up even higher.

The prosecutors in Romans’ case were able to use testimony from his fellow dealers and his ex-wife to argue that Romans had done all three of those things. Romans maintains his innocence in accordance with these charges, and says the other dealers lied in exchange for reduced sentences. But the judge didn't believe him. According to the sentencing guidelines, he was now subject to a life sentence.

All hope wasn't yet lost for Romans. In 2005, the Supreme Court ruled in a landmark case, United States v. Booker, that judges do not have to comply with the sentencing guidelines. And as the country’s views on drugs, and, in particular, marijuana, have begun to shift in recent years, many judges in drug cases have chosen to mete out sentences that are lighter than what the guidelines recommend.

Romans' sentencing hearing took place in February 2013, two years after his transfer to the Texas jail. Standing before Judge Marcia Crone, Romans’ court-appointed lawyer, James Whalen, made a last-ditch plea for leniency.

“I -- I have been doing this long enough and I have had clients receive life sentences,” he said in a halting cadence captured in the court transcript. “And the one thing they've always -- the common denominator in all those life sentence cases is they murdered somebody.”

“Well, you can get life for not murdering people,” retorted Crone.

“I know you can,” said Whalen. “But to me this is not that case, Your Honor.”

Crone wasn’t impressed by Whalen’s argument. “I think a life sentence is appropriate in this instance,” she said.

Crone specifically noted that she didn’t support the recent efforts made by states around the country to loosen restrictions around pot. “I don't agree with it, and the federal government hasn't changed the marijuana laws,” she said. “I think it's misguided, the places that have. So I don't agree with that. And I'm not going to look at trends.”

Romans entered prison in April of last year. A few weeks after his arrival, his parents and sister suddenly stopped getting calls from him. They later found out that a group of inmates had rioted, prompting the guards to lock everyone in their cells for a two-week stretch.

Several months after that, according to Romans' sister, Elizabeth Bishop, Romans returned from lunch to find guards in his cell and blood spattered all over the walls and the beds. “Somebody attempted to murder his cellmate,” his sister explained.

Romans has never been convicted of a violent crime, and Bishop, for her part, insists he’s as gentle as can be, despite the evidence that he had guns and ran the smuggling ring. “Scared of a spider” was how she put it.

And yet he's sentenced to spend the rest of his life under the same roof as men like Ricky Mungia, a Texan who went on a shooting spree with some white and Latino friends in 1994, hunting down black men in the streets of Lubbock and shooting them from a car with a short-barreled shotgun.

According to the federal Bureau of Prisons, it costs an average of $30,000 a year to keep someone confined in a high-security lockup, and as a person ages and requires more medical care, the cost increases. “We’re talking 40, 50, 60 thousand dollars a year to keep someone in a cell until they die, when they could be working and paying into their insurance,” Zlotnick said. “It’s insane.”

Last August, the U.S. Department of Justice issued a memo advising prosecutors to avoid asking judges to give harsh sentences to low-level drug defendants. Drug-reform advocates hailed the memo as an important step toward scaling back the drug war, but it’s unclear whether it could help someone convicted of a high-level offense, like Romans.

Romans still says he was just a middleman, and has filed an appeal. On Tuesday night, he used the last of his monthly allotment of 300 phone minutes to talk to The Huffington Post. Asked how he felt when he learned he would be getting life, he said, “I couldn’t believe it, I couldn’t believe it.”

“They gave me a life sentence for marijuana,” he said. He seemed truly surprised by his predicament.

After a few more minutes the phone went silent.