After these interrogations, they should just beat them senseless or execute them. It's clear they have no remorse or understanding of their fatal actions. A society ran by them under no repercussions or recourse results in outcomes like that.
I get it. There are many foods which I enjoy while they are largely reviled by those whom have been forced to consume them by circumstance and privation
People never seem to compare these statistics to their expectations. If there were no correlation at all between race and relationships, then white Americans would still marry whites the most because they are the majority. If anyone selects a random mate it will most likely be a white person.
And conversely, if you imagine, say, a black man who is equally likely to marry a black woman as a white woman, that means he still has significant racial bias toward black women. He would be more likely to marry white than black, if there were no bias.