Russia-Ukraine war: Why world leaders labelling President Vladimir Putin war criminal could help prosecute him - expert

World leaders have been labelling Russian President Vladimir Putin a war criminal for the monstrosities committed in Ukraine. A Kiwi expert on atrocity prevention says while these are not currently legally justified, they could help Putin be prosecuted. 

Associate Professor of Law at American University Rebecca Hamilton told Newshub Nation on Saturday that while Putin has not gone through a legal proceeding to prove he is war criminal, the term being used could help hold him accountable in the future.

"There is some degree to which these characterisations can help build the political will that is needed to ensure that prosecutions do go forward," Prof Hamilton said.

Since Russia launched a full-scale attack on Ukraine in February, evidence has emerged of atrocities being committed in the war-torn country from mass graves, targeted civilian deaths and rape by Russian soldiers. 

The images and reports emerging from Ukraine have caused many people to label Putin as a war criminal, including US President Joe Biden and UK Prime Minister Boris Johnson.

However, Prof Hamilton said she is much more concerned about what politicians are doing to stop Putin than what they say about him.

New Zealand has condemned Putin's actions by imposing sanctions on Russia and sending military aid to help support Ukraine. 

Prof Hamilton said Jacinda Ardern and other politicians that have not publicly called Putin a war criminal reflect a legal reality that there hasn't been a legal proceeding.

"I think Jacinda Ardern and other politicians, she is not alone in this, have been more measured in their remarks are probably just listening better to their legal advisors," Prof Hamilton said.   

Prof Hamilton said while it is straightforward that these atrocities are happening in Ukraine, it takes time and a lot of evidence we do not have at this stage for a prosecutor to link the crimes to an individual perpetrator and up the chain of command.

But Prof Hamilton said she is confident there is enough evidence to prosecute Putin for the crime of aggression for the initial decision to go to war.

"We have enough evidence already to go ahead with a prosecution of Putin for the crime of aggression for the decision to wage war in the first place, to invade another sovereign nation."

She said it is the original crime that everything flows from so it is important that Putin gets prosecuted for the crime of aggression in addition to what everything else he may be responsible for.

Prof Hamilton said it is important to start building legal cases against Putin now, but while he is in the Kremlin it will be hard to prosecute him. 

Putin would have to travel to another country or there would have to be a change in Russian domestic politics for him to be arrested, but Prof Hamilton said history shows that we get there in the long run.

"All of those I fully appreciate seem inconceivable in this moment," Prof Hamilton said. "So I think we have to retain some hope that in time justice will happen."