It is a fact that there is considerable racism in the US. When an American cop shoots an unthreatening person of a different race, racism must always be considered as one of the possible motivating factors. In particular, given that it is known that many (not all, by any means) white Americans regard darker skinned men (there is sexism as well as racism)  as inherently threatening, it is reasonable to regard racism as a likely factor when a white cop shoots an otherwise unthreatening black man. Yes, this is racial profiling, and because it is just probabilistic, racism should be suspected but should not be presumed without evidence.

On the other hand, when black cop shoots white person, I wouldn't rule out racism. Every case must be examined on its own merits.