The four men accused of carrying out Russia’s deadliest terror attack in decades appeared in a Moscow court on Sunday night bandaged and battered. One entered with his partially severed ear covered. Another was in an orange wheelchair, his left eye bulging, his hospital gown open and a catheter on his lap.
Many people around the world, including Russians, already knew what had happened to them. Since Saturday, videos of the men being tortured during interrogation circulated widely on social media, in what analysts called an apparent retaliation for the concert hall attack they are accused of committing last Friday, which killed at least 139 people and injured 180 more.
One of the most disturbing videos showed one defendant, identified as Saidakrami M. Rajabalizoda, having part of his ear sliced off and shoved in his mouth. A photograph circulating online showed a battery hooked up to genitals of another, Shamsidin Fariduni, while he was being detained.
How the videos began circulating was not immediately clear, but they were spread by nationalistic, pro-war Telegram channels that are regarded as close to Russia’s security services.
Though the goriest clips were not shown on state television, the brutal treatment of the defendants was made clear. And the decision by the Russian authorities to showcase it so publicly in court, in a way they had almost never done before, was intended as a sign of revenge and a warning to potential terrorists, analysts said.
In Russia’s recent history, videos of torture were not shown on state television, said Olga Sadovskaya of the Committee Against Torture, a Russian human rights organization.
“There were two intentions” to circulating the videos, Ms. Sadovskaya said. “First, to show people who could plan another terrorist attack what could happen to them, and second, to show society that there is revenge for all that people suffered in this terrorist attack.”
She and other analysts said the flagrant display of the tortured demonstrated something else: the extent to which Russian society has become militarized, and tolerant of violence, since the war in Ukraine began.
“This is a sign of how far we have gone with accepting the new methods of conducting a war,” said Andrei Soldatov, an expert on Russia’s security services.
International surveys have shown that societies tolerate violence against people they perceive as the worst offenders, including terrorists, serial killers and perpetrators of violent crimes against children.
Nevertheless, Ms. Sadovskaya said the videos being aired on TV represented a new low for the Russian state.
“This shows that the state and authorities demonstrate that violence is acceptable, that they normalize the torture of a certain subject,” she said.
The Kremlin’s spokesman, Dmitri S. Peskov, declined on Monday to comment on the torture allegations during a briefing with journalists. But former President Dmitri A. Medvedev, who currently serves as the deputy chairman of Russia’s Security Council, said, “Well done to those who caught them.”
“Should we kill them? We should. And we will,” he wrote on Telegram on Monday. “But it’s more important to kill everyone involved” in the attack. “All of them: those who paid, those who sympathized, those who helped.”
Ivan Pavlov, a lawyer who used to defend difficult national security cases before being forced to flee Russia, said torture had long been used in terrorism and murder cases, mostly out of sight. Once the news about torture filters through prisons, he said, it lets “other people know that if you are accused of terrorism, the special forces will torture you. So it works like prevention.”
The court hearings on Sunday were unusual because the torture was so brazenly put on display, Mr. Pavlov said.
“Before, they hid it from the general public, but now they are not because the general public is ready for violence,” he said. “It is no longer something extremely unpleasant for the general public because of the war.”
Russia is no longer party to the European Convention on Human Rights, but the Russian Constitution outlaws torture. It is also part of the United Nations Convention Against Torture.
Since torture is a crime both under international law and in many countries, defense lawyers would normally seek to have any testimony extracted under torture thrown out because it is notoriously unreliable, said Scott Roehm, the director for global policy and advocacy a the Minnesota-based Center for Victims of Torture, which works around the world.
The black-and-white legal finding that torture is a crime, a fundamental aspect of international human rights law, came under pressure in the United States after the Sept. 11 terrorist attacks, Mr. Roehm noted. So the military commissions that dealt with cases at Guantánamo Bay had to take into account that some of the evidence was tainted by torture.
“Torturers don’t spend a lot of time thinking through the various consequences of their actions,” said Mr. Roehm, especially in the aftermath of an attack like the one in Moscow. “I think a torturer’s mind-set is often a mix of a good degree of revenge and an entirely misguided, ignorant assumption that you could get somebody to ‘confess’ under torture, and that confession can be used to convict them.”
Trials of extremists in Russia are generally closed, as were most of the hearings on Sunday, so it is impossible to know to what extent defense lawyers have objected to the practice. Most Russian judges would likely ignore it in any case, Mr. Pavlov said, because they know ahead of time what is expected of them in terms of sentencing the accused.
Indeed, the judge in the case of Muhammadsobir Z. Fayzov, 19, who seemed barely conscious at times, almost entirely ignored the fact that the defendant was in a wheelchair in an open hospital gown, a plastic container holding urine from his catheter in his lap. The only time the judge acknowledged it was to order two doctors, accompanying Mr. Fayzov, removed from the courtroom with the rest of the public when he closed the hearing, according to the report by Mediazona, an independent Russian news outlet.
The blatant flaunting of the battered suspects on Sunday was particularly egregious, Mr. Pavlov noted. “These are sad circumstances, of course,” he said, “but they made a circus out of the trial.”
Mr. Soldatov, the security services expert, said the torture and the official response to it was a signal to the military that gruesome violence was now acceptable and encouraged.
By releasing videos of the torture, he said, the authorities are “sending this message of intimidation to everyone who is not on the Kremlin’s side — and sending a very encouraging message to the military and security services that you are on the same page.”
Ruslan Shaveddinov, an activist and investigative journalist affiliated with the Anti-Corruption Fund of Aleksei A. Navalny, the opposition figure who died in a Russian jail last month, called on Russians to condemn both the terrorists and the torture used on them.
“It is important to say: Torture is not normal,” he tweeted on Sunday. “Torture as a phenomenon should not exist. The cops and the state today torture a terrorist, they see approval of this method, and tomorrow they will torture an activist, journalist, anyone else. They don’t know any other way.”
Aric Toler contributed reporting.