An expert's outlined how a head of state's actions could be considered war crimes. 

Photos and video have appeared showing bodies shot at close range in Ukraine's Bucha, left after Russian troops retreated.  

US President Joe Biden wants Russian President Vladimir Putin put on trial. 

Otago University senior law lecturer Stephen Smith told Andrew Dickens direct orders could qualify as proof ... but other principles could also apply. 

“If the leader of the country should have been controlling his military more closely, I guess you could say, but sort of was neglecting that duty, that could qualify as well.” 

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