Bottom line is I don't believe in corporal consequences for speech. Getting fired from a job I consider corporal punishment because it affects your livelihood which in turn affects your survival. I believe speech should have no consequences beyond social. Meaning, yeah your coworkers can call you a jerk but your boss can't fire you for being a jerk unless being a jerk is a direct hindrance to your job duties being fulfilled.

Using your earlier KKK cop example. If a cop is a KKK supporter, but performs his job duties without any evidence of racial discrimination, then I say let him continue to do his job. We should measure the fitness of a person and their worth to society on their actions not their words.

IMO I don't think it would be too hard to come up with a law based on those principles, but I'm not a legislator so it's above my paygrade.