In April 2014, University of Arizona assistant professor Dr. Sue Sisley made headlines after winning federal approval to test marijuana on veterans suffering from PTSD. That made her the only academic in America to get a government go-ahead for cannabis research—and one of just 15 people to get such approval in the last two decades. The occasion hailed not only as a historic shift in public policy for the marijuana community but a huge victory for the 21.2 million veterans living in the U.S. today.

Three months later, it’s turned to defeat.

Terminated from the University of Arizona last week, Sisley is now both jobless and moneyless—stripped of the institution, people, and funding on which her study hinged. America’s only federal-approved academic marijuana researcher just got the floor pulled out from under her.

Who is to blame?

The first time Dr. Sisley listened to a veteran with PTSD describe self-medicating with weed, she ignored him. A lifelong conservative, her perception of marijuana was reduced to stoners getting high for fun. “[My patients] wouldn’t even talk about it with me—they knew I would disapprove,” she tells me.

But the stories didn’t stop. Recurring nightmares, insomnia, loss of interest, anger, sadness, and irritability—the hallmark symptoms of Post-Traumatic Stress Disorder—were paralyzing her patients. The medicine wasn’t working. Zoloft and Paxil, the only two FDA-approved medicines for the condition, left the soldiers feeling numb, dizzy, and in a constant state of fog. Marijuana, many found, was stronger than all of them combined.

In time, her office became a pseudo-confessional for former soldiers who’d turned to the black market for medicine. “Veterans were having the courage to tell me they were using this plant to successfully treat the whole constellation of symptoms,” says Sisley. “After 10 years, I couldn’t ignore it.”

Convinced by the fact that these “highly principled” men and women were actively choosing to break the law, Sisley set out to gather objective data that might corroborate their anecdotal evidence. Her game plan: a triple-blind randomized control trial of marijuana’s effect on 70 veterans with PTSD.

Requesting to study the medical value of a so-called “schedule I substance” like marijuana challenges the very core of its classification, which rests on the assumption that the substance has no medical value. The move not only implies that the government is wrong—but requests its help in trying to prove it. In two decades, only 15 researchers have won the approval to test the efficacy of marijuana on humans. Dr. Sisley’s, centered on a population that Americans have an emotional connection to, had as good a shot as any. “Our veterans are so coveted. I thought the sense of urgency would capitulate it to the front,” she says.

At first, it did. The stamp of approval from the Federal Drug Administration, one of three agencies that must sign off, came within days. The agency was not only cooperative, but “welcoming” of the research. The next step, getting approval from Department of Health and Human Services—which then permits the National Institute on Drug Abuse to supply research-grade marijuana—wasn’t so easy. When months went by, then years, Sisley assumed her request would be stuck permanently in the HHS review process.

But then, something strange happened. News organizations—in particular, CNN—began to reverse their long-standing hostility to marijuana. And that created an enormous amount of pressures on federal bureaucrats to do the same. Dr. Sanjay Gupta, CNN’s medical correspondent, went on air to apologize to the American public for “misleading” them when he claimed marijuana had no medical value. In the interview, Gupta directly (and wrongly) implicated NIDA for not providing the supply of marijuana. The statements were inflammatory enough to garner a response from NIDA Director Nora Volkow, who shifted the blame to the Department of Health and Human Services—without whose approval she cannot grant access to research-grade marijuana.

Three days after the media frenzy, Dr. Sisley got a letter from the HHS. Her study had been approved.

For veterans like Specialist E4 Sean Kiernan, who survived four years of war before almost fatally overdosing on GHB and PTSD drug Lamictil, it was long overdue. In a chilling picture taken by his wife, a gray-looking, unconscious Kiernan is seen lying on a hospital bed with a breathing tube and IV. After a cocktail of PTSD meds failed to alleviate his symptoms, Kiernan says he was looking for a way out. “I took a significant amount of [GHB and Lamictil] in hopes of everything in my head would just go away,” he tells me. In a coma for five days, he decided to try cannabis upon his release seven days later. “Marijuana has given this family of six their Dad and my husband of almost 23 years back,” Kiernan’s wife, Christina, says.

It was stories like Kiernan’s that propelled Sisley forward. “As much as I’m grateful that the study’s been green-lighted, I think our veterans are sickened that it took three years after FDA approval to get that far,” she said in an interview weeks after the March 2014 approval. In the time she’d waited, 24,000 veterans had killed themselves. “How many of these vets could this have helped, or saved?” she said. “I’m grateful that I got approval, but the battle isn’t over.”

She was right. Within weeks, a new roadblock appeared in the form of Arizona State Senator Kimberly Yee. In a legislative session of the Arizona Senate Education Committee, which she chairs, Yee blocked a hearing of House Bill 2333, which had been unanimously approved by the House. This was a landmark piece of legislation that would permit medical marijuana cardholder fees to fund Sisley’s study. Instead, Yee said, the funds should be used to prevent drug use. “I believe these funds would be better used to educate our general population, especially our youth, about the harms of recreational marijuana,” said Yee.

Sisley, who had managed to win over a skeptical federal government, was now facing an even tougher opponent. Incensed by Yee’s decision, the local medical marijuana advocates launched a recall effort against her.

Yee fought back, claiming she was in favor of marijuana research and had only blocked this bill because she was “concern[ed] about limited state funds.” Those supporting the research, she said, had assured her that funds would be coming from the federal government or private donors. “Today, they have turned their story around and have broken their promise,” said Yee.

But Yee’s recent record tells a different story. In late March, days before Yee came out in support of anti-marijuana legislation, Fox 10 News exposed direct actions she took to hinder medical marijuana progress. “[She] feels backers of the scientific study want to legalize marijuana, as in Colorado or Washington state,” the article reads, citing two bills designed to toughen legislation on medical cannabis. One, sponsored by Yee, aimed to ease regulations on the seizure of medical marijuana by allowing police to “eliminate” it if they deemed it simply “hazardous.” Yee declined to comment on these specific allegations.

Also looking to undermine marijuana research behind the scenes was the president of Arizona’s State Senate, Republican Andy Biggs. In a March legislative session, Biggs added an addendum to budget bill HR2703 proposing that no university resources or general fund monies ever go to support marijuana research. When Sisley released a photo of the addendum, taken by a friend in the legislature, reporters flooded Biggs with questions. In the absence of a response, Biggs removed it.

On April 4 at 5 p.m., Sisley says, she got a call from Skip Garcia, vice president of the university’s Health Sciences Center. He claimed that Biggs called the president of the university and demanded she hand over all records of Sisley’s emails, texts, and communications. “[Biggs] was concerned and upset that I was somehow engaging in political activity,” says Sisley. (Biggs did not return multiple requests to comment for this story.)

Over the next few months, Sisley watched the university, whose Institutional Review Board had approved the study in 2011, become increasingly wary of her plans. Requests from Sisley for a location to conduct the study were continually tabled. Officials told Sisley they were worried—despite the federal government’s approval—that it might not be legal to do it on campus. Without a set location, Sisley couldn’t get the DEA license she needed (the final agency’s approval) to move forward. Without funds from the state, it was a moot point.

When Sisley received a letter from the university saying they were not going to renew her contract, she wasn’t the least bit surprised. “They made every effort they could to thwart the study at every turn,” she says.

The university, which responded to The Daily Beast in an email, disputes this. “Sorry, but the University of Arizona does not comment on personnel issues,” wrote spokesman George D. Humphrey. “In regard to marijuana research, in general, in 2013, the UA championed state legislation to ensure that universities could perform medical marijuana research on campus.” Sisley says she’s heard this before. “The University of Arizona can say whatever they want about their love of pot research but the proof is in their inaction, not their words.”

But even more than the university, it’s the lawmakers behind them that Sisley holds responsible. “These hyper-conservative lawmakers in Arizona are fundamentally opposed to marijuana research,” she says. “Some have even gone on record with reporters to say weed research is a strategy for achieving marijuana legalization. They don’t want to see any universities resources going to support this work.”

As of Thursday, the university’s decision stands. Jason Flores-Williams, the lawyer representing Sisley, is determined to change that. In the next seven days, Flores-Williams will be filing an administrative appeal to have Sisley reinstated. If the administration refuses, he will prepare for litigation. “We can independently corroborate Dr. Sisley’s outstanding performance reviews and show that she was generally recognized as being one of the most respected teachers and doctors on staff,” Flores-Williams tells me of what he believes to be her unlawful firing. “The ones who are being injured here are veterans, people who have already sued the country.”

As my final phone call with Sisley winds down, she tells me she’s just received a discouraging email. It’s from another university. One that a few years ago commended her study and offered their help, should she need it. Without reading the email, Sisley sums it up: Sorry, we’re not interested.

As Sisley awaits the fate of her marijuana research, she’s still baffled by how difficult it is to study a drug that’s medically legal in 23 states. “It’s so clearly about politics, not science. Republicans feel like this is the pill they need to die on,” she says. “We keep asking, ‘What are you afraid of?’”