ACAB stems from the police's tendency to always back each other, regardless of their behavior. If they would start policing their own coworkers' conduct, stopping their own from behaving badly, and testifying against each other when appropriate, the ACAB meme would die.

I would say the person is not necessarily a bastard until they put on the uniform. Always exceptions, but we all have to work and unfortunately most honest people's professions today are ethically dubious to varying degrees. Especially in tech.