After today's events, there is a lot of speculation that Flight MH17 was brought down by surface to air weapons.
Witnesses appear to have heard the loud explosions before the flight crashed, and whilst obviously unfounded for the time being, reports claim that the only parties who would have been in a position to facilitate this would be Separatist forces: whom it's almost unanimously agreed are being supplied with equipment by the Russian state.
It's most likely that, if it was shot down, it was shot down by mistake: however, how culpable will the Russian state be if this is revealed to be the case? Would they be held accountable for this act, and would they have committed a war crime?
Is their rhetoric and political distancing from separatists enough to legally grant immunity, or will their supplying the weapons used implicate them directly in a 'terrorist' act?