Captured Russian Pilot Says He Was Ordered to Hit Civilian Targets

But that was made on the assumption that the war itself was being prosecuted under those conventions. The idea that a solider might genuinely want to denounce his superiors and declare the war illegal... I just don't think that occurred to them.

There's no really good way to determine whether that's the case here, not without a fuller inquiry that will at best happen after the fact. And maybe that's the best you can hope for: to have accusations of rule-breaking settled later since you can't really apply interventions at the time. If these soldiers are doing this of their own volition, then the rule hasn't been violated. If they are... then we're all in a lot of trouble since it will get progressively worse.