Judge Only Individuals as Individuals

To judge someone 'on the content of their character' they first have to agree to act as an individual.

As soon as someone pulls the race card, go ahead and judge them according to their race.
If you want to get technical, they have individually chosen to assimilate race as part of their individual identity, and as such promising to behave primarily as part of that group.
It's not "profiling" anymore. They're telling you they are mainly their race. You have permission. 

That said only licensed, professional aristocrats should be judging anyone at all.
If you're part of a society that lets peasant character judgments affect...well...anything, consider perhaps GTFO. Maybe go and stay go, for the sake of your own well-being.