How can one deal with bosses who are bias?

really it is a very sensitive Question :)anyway as all are knows this case we always see it in all environments Unfortunately , so in this situation and if you are faceing this try to open direct channle with your direct manager and discuss all thing, here try to give solutions more than be complainer, if this not work you may discuss this with Upper managements, if all you did with no results allow me to say you have a bad luck.

don't interact too much & just mind our own business

work with team to reach company goal

By Smile/gently/Smallness/Knowledge..

I believe working according to company's rules and policy will not get you in a troubles with bosses regardless thier behavior.

by opening face to face discussion if its not work try to discuse by the apper management

connect,convey and convince