Nice little bumper sticker, but I think tolerance is actually listening to how another person does or wants to do things and giving their ideas consideration. Tolerance is not incapable of pointing out what's unworkable or unjust in the other's way. I need not tolerate racism, for example, but neither must I simply tell racists to do things my way.
Note, too, that the differences among the crimes of killing are mostly in the prescribed sentences for those convicted of committing them. When one pleads to manslaughter to get out of a murder charge, one is not changing the nature of the act of killing.