True education is occurring. For the few who resist being accountable, it may take longer and certainly more effort, but over time it will be the very, very few who refuse ever to join the ranks of the fair. Peer pressure and the success of the confrontations with accountability become a powerful force. However, some groups, some schools, some age groups, may contain those very, very few. When time, effort, every possible means have failed to get them on board, then steps need to be taken to remove them from the scene.
Some intervention is needed.
Those children should not re-enter the home or school until they have successfully begun to open up to fairness and are willing to play by those rules. Only then can they be given a second chance. If they still refuse, then interventions are their lot. They cannot be allowed to disrupt or terrorize their family or their school. It is not good for them to have that kind of abusive power and of course it is not good to allow others to be abused.