Russian investigative journalist Ivan Golunov made his career writing the news, revealing corruption among Moscow’s elite for the news site Meduza. But he became the subject of headlines himself last week, after he was arrested on trumped-up charges of drug trafficking that could have landed him 20 years in prison.

After an outcry and scrutiny from Russia’s remaining independent media, authorities eventually conceded a lack of evidence on Tuesday. When he was released that day from house arrest, activists hailed it as a rare victory amid a sea of repression.

But they also say he should never have been arrested in the first place. Golunov was stopped on the street in Moscow on June 6, handcuffed and bundled into a police car. Police then strip-searched him and allegedly beat him. They then said they had found a packet of mephedrone in his bag, and charged him with conspiracy to traffic the drug. His disappearance initially went unreported, and when his lawyer was finally able to see him after more than 12 hours, Golunov said he had not been allowed to eat or sleep. By the time the journalist appeared on June 8 in a Moscow court, where he was sentenced to two months of house arrest awaiting trial, doctors suspected he had a concussion and broken ribs.

Cracks soon started to appear in the official story, however. Photos purporting to show a drug lab in Golunov’s apartment were removed from a government website after his journalist colleagues established they were taken elsewhere. On the streets, meanwhile, a wave of support was growing. One-person vigils—which, unlike other forms of protest in Russia, don’t require a permit—were held on a rolling basis, despite police intimidation. Video footage posted on Twitter showed crowds of supporters lining up to “change shifts” with a lone picketer. And on June 10, three of Russia’s biggest newspapers each carried the same front-page headline: WE ARE IVAN GOLUNOV.

Russian authorities detain a man during a rally in support of journalist Ivan Golunov on June 12, 2019 in Moscow Sergei Savostyanov—Sergei Savostyanov/TASS

“We have grounds to believe Golunov is being persecuted because of his journalistic activity,” his editors at Meduza said in a statement. Ivan Kolpakov, editor in chief of Meduza, tells TIME that he believes Golunov’s ordeal was prompted by one particular piece he was working on as recently as last week.

Golunov might be a free man now, but intimidation of journalists is common in Russia, which is ranked 149th out of 180 countries for press freedom by Reporters Without Borders. “Ivan’s arrest is just a part of the Russian system,” Kolpakov says.

But in this case, Golunov received an unexpected wave of support. His incarceration became a test of solidarity among Russian journalists, who rallied to his defense. In front of the country and the world, they effectively dismantled the police narrative. Even some reporters in the state-run media stood up for Golunov. Eventually, the Russian Interior Ministry stepped in to order his release. The officers involved in his arrest have been suspended.

Nevertheless, their tactics revealed something about the way public discourse is stifled in Russia today. “The easiest way to put anyone in prison in Russia is to plant drugs in his bag,” Kolpakov told TIME shortly before Golunov was released. “It means that he immediately goes to prison. It means that his reputation is immediately destroyed. It means it’s going to be a dirty case.” In Russia, reporters routinely face intimidation, and most newspapers and TV channels avoid criticizing powerful figures in politics and business.

But Golunov was determined to do his work. “I think he had a lot of powerful enemies,” Kolpakov says. “I would say many people were not pleased by what he wrote. Many people did not want to appear in his pieces, because it’s the easiest way for a corrupt person to become famous.”

In a recent story, Golunov had presented evidence to show the deputy mayor of Moscow had embezzled public money, with which he and his family were able to buy nine penthouses in the city.

And Gulonov wasn’t a stranger to receiving threats, either. “He was threatened in April 2018 by a group of people he wrote about, because of one of his articles,” Kolpakov tells TIME. “He was threatened systematically and I’ve heard that a couple of months ago he also got some other threats from the same people.”

The most recent threats, Kolpakov says, weren’t about a published piece, but an-as-yet unpublished investigation Golunov was working on for Meduza.

In a stroke of luck, Golunov filed that story just hours before his arrest. Now, Meduza is preparing to publish it. His arrest virtually guarantees that investigation will reach a wider audience than ever before. “He is a lucky guy,” Kolpakov says. “For the first time in his life, he didn’t miss his deadline.”

Correction, June 12:

The original version of this story misstated the type of drug police said they found in Ivan Golunov’s bag. It was mephedrone, not methamphetamine.

Write to Billy Perrigo at billy.perrigo@time.com.