>or that police dogs are more racist than police officers
I think the point is that police dogs are supposed to be LESS racist (and more objective) than police officers, since they can be used as probable cause for a search (unlike an officer's hunch).
Indeed. The article speculates that police dogs may pick up on their handlers' prejudices; but it does not show that. And even if dogs do pick up some prejudice, they may still be sufficiently objective to be used as probable cause.
I think the point is that police dogs are supposed to be LESS racist (and more objective) than police officers, since they can be used as probable cause for a search (unlike an officer's hunch).