Abuse is never okay. It doesn't matter if it is child, elder, spousal or animal. Any person who abuses another living being is the lowest form of scum that walks the earth. To my way of thinking that individual should be exposed at least to the same intensity of abuse that they inflicted.
Some will say that these individuals were possibly the victims of abuse themselves. Well that may be so but it still does not justify them abusing others. To me the ultimate punishment should be death, not rehabilitation not jail time but death. They are not human; they are lower than any form of life and therefore do not deserve to live.