Nothing really justifiable. It's been a while since I read this (I only came back due to the raws now almost at ch90) so correct me if I'm wrong... But IIRC they're dealing with elite breeding prejudice (they can't be together because black cat is non-alpha so the elders/superiors will force the white cat with someone else for mating) ...
To counter that, they've been experimenting on other people including children to see if they can transplant the alpha genome to another cat like a shared cell. Which lead to a lot of deaths and deformation in the process.
The white cat acts like it's for the greater good (being able to turn betas into alphas) but they've been conscripting and kidnapping children anyway from the lower class to the slums knowingly signing them their death warrant.

Does anybody know the two white and black cats backstory? Cause It has to be justifying enough for them to do this