A Russian soldier who pleaded guilty to killing a Ukrainian civilian was sentenced to life in prison on Monday in the first war crimes trial since Moscow invaded three months ago, unleashing a brutal conflict that has led to accusations of atrocities, left thousands dead, driven millions from their homes and flattened whole swaths of cities.
In a rare public expression of opposition to the war from the ranks of the Russian elite, a veteran diplomat resigned and sent a letter to foreign colleagues in which he said he had never been so ashamed as on the day Moscow invaded.
Since then, a stiff Ukrainian resistance has bogged Russian troops down, thwarting their attempt to take the capital, and the two sides are now fighting village by village in the eastern Donbas region. As the war rages on, judicial authorities worked to hold one low-level soldier to account in a speedy trial.
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An outside expert said the unusual wartime trial appeared to be fair, but a Ukrainian civil liberties advocate said Sgt. Vadim Shishimarin's life sentence was harsh.
Shishimarin, 21, pleaded guilty last week to shooting a 62-year-old man in the head in a village in the northeastern Sumy region in the early days of the war. He apologised to the man's widow in court.
Shishimarin's defence attorney, Victor Ovsyanikov, argued that his client had been unprepared for the "violent military confrontation" and mass casualties that Russian troops encountered when they invaded Ukraine. He said he would appeal.
Volodymyr Yavorskyy of the Centre for Civil Liberties said that the public was interested in "a crystal clear process in compliance with all legal norms."
"The trial left many questions," he said. "This is an extremely harsh sentence for one murder during the war, and the very qualification of the crime was wrong."
But Aarif Abraham, a UK-based human rights lawyer, said the trial the was conducted "with what appears to be full and fair due process," including access to a court-appointed attorney.
This is only the first charge to come to trial. Ukrainian prosecutors are investigating thousands of potential war crimes, as the world has pushed for Russia to be held accountable for its invasion. Russian forces bombed a theatre where civilians were sheltering and struck a maternity hospital. In the wake of Moscow's withdrawal from towns around Kyiv weeks ago, mass graves were discovered and streets were strewn with bodies in towns such as Bucha.
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Other, more difficult cases may need to go to an international tribunal, said Abraham, who specialises in international criminal law at Garden Court North Chambers in Manchester.
"The International Criminal Court will have jurisdiction to try those most responsible for alleged war crimes, crimes against humanity or genocide, where Ukraine is unable or unwilling to do so," he said.
Shishimarin had told the court that he at first disobeyed his immediate commanding officer's order to shoot the unarmed civilian but had no other choice but to follow the order when it was repeated forcefully by another officer.
Abraham, however, noted that following a order would not be a defence under the law.
Speaking to reporters before the sentencing, Kremlin spokesman Dmitry Peskov said that Moscow was concerned about the Russian soldier's fate but was unable to defend his interests "on the ground."
"But this doesn't mean that we won't consider the possibility of continuing attempts (to defend him) through other channels," he said.
Russia and its allies have also threatened to bring war crimes charges against Ukrainian soldiers. The head of a Russia-backed separatist region in eastern Ukraine said that fighters who made a last stand in Mariupol would face an "international tribunal."
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Russian authorities have repeatedly levelled vague accusations of war crimes against the fighters who holed up at a steel plant in Mariupol, and seized upon the far-right origins of one of the regiments there as part of an effort to cast the invasion as a battle against Nazi influence in Ukraine.
Russia's claim to have taken full control of Mariupol in recent days was its biggest victory of the war yet.
Family members of the fighters have pleaded for them to be given rights as prisoners of war and eventually returned to Ukraine.
Russia's Deputy Foreign Minister Andrei Rudenko said Monday that he "allowed for the possibility" that the fighters could be exchanged. "I allow for any possibility that doesn't contradict common sense," Rudenko told reporters.
Zelenskyy, meanwhile, called for "maximum" sanctions against Russia to punish it for the war.
In a a video address to the World Economic Forum in Davos, Switzerland, he said that sanctions needed to go further, including an embargo on its oil and cutting off trade with Russia completely.
On the battlefield, Russian forces have stepped up their bombardments in the Donbas, where they are engaged in a slow slog. Many civilians have had to flee their homes. The United Nations said the conflict has helped push the number of people displaced worldwide to the highest level on record level, with more 100 million people driven from their homes across the globe.
"We haven't been able to see the sun for three months. We are almost blind because we were in darkness for three months," said Rayisa Rybalko, who hid with her family first in their basement and then in a bomb shelter at the local school before fleeing their village of Novomykhailivka. "The world should have seen that."
Her son-in-law Dmytro Khaliapin said heavy artillery pounded the village. "Houses are being ruined," he said. "It's a horror."
