My personal observation is that most people, regardless of culture context, tend to put stigma mainly on the victim of a violent act and not (that much) on the perpetrator.
It is always the victim who feels shame and embarrassment in public and it is never the perpetrator. As far as the perpetrator is concerned, things are clear - malignant egoism and narcissism prevents them from feeling any remorse or shame.
But why does the victim feel shame? Why is the public response of mocking or insulting the victim for being a victim and not the perpetrator for acting violent?
(I have my own hypothesis: being a victim is a display of weakness, which is unconsciously perceived (on an evolutionary psychology level) as threat for the survival of the social group. A weak individual has no use as far as physical combat survival is concerned. A strong, albeit criminal individual is not that useless: in times of peace he could be kept imprisoned, but in times of war, he could be deployed.)