Board Thread:Theories and Speculation/@comment-31186252-20170219013048/@comment-734582-20170219100840

BakumatsuWarrior wrote: Oro needs to be executed for the countless atrocities he's committed throughout his life. They owed him one for his indispensable help in the War. Without Orochimaru, mankind would've been done for. Without his experiments, Oro never could've given that help. Karma-wise, it cancels out.

I guess that's the assumption the Villages work under: Orochimaru's slate got wiped, he didn't reform into an ultimate good guy.

Also, consider now that he has Zetsu cells and considering the many things he saw in the War, he has decades of research to do (that doesn't involve murdering innocent people)