They're pretty well documented in non-Russian media, with videos of torture rooms, interviews with torture and rape victims, medical examinations of related injuries, and mass graves with bodies showing clear evidence of torture.

I am a bit surprised that you are asking for proof, given the scale of the reporting.

Bet on different horses, to start. The propping up of dogshit puppets and the recapitulation of the vertically-integrated corruption of Russia’s political & economic model was badly executed in Ukraine. The FSB spread its money in the wrong places, and there was little effort to sway hearts and minds at the retail level. Russia fucked this part up all by themselves.

Second, fight the war like professionals and honor modern conventions on rape and torture. Once Russia got so far behind the eight-ball that Putin felt a full invasion was necessary, Russia chose to fight and subjugate like it was the 16th century, with an army seemingly unbound by morality or professionalism. On this basis alone, I’ll continue to support any efforts to eject Russia.