Police harder on their race?

Today I was stopped by a Mexican cop, he umed I was tagging. I wasn't, I was searched twice and had the area where he saw me looking at a wall searched by him and other cops that showed up to help. He just could not believe that I looked at the wall for no reason. This isnt the first time a person of higher authority who is the same race as me has been extra hard. The way he talked to me, he umed I was just another lowlife gangbanger. He wouldnt believe me when I said I wasnt from anywhere. My history is clean, ive got no tattoos or affiliation with any gang. So is it only me that has had bad encounters with cops of the same race?