Being racist and having implicit biases are in fact two different things. Every human DOES have implicit biases. Our brains just work that way. We lump other people into categories to process quicker, despite this often being inaccurste. Our implicit biases are shaped by the communities we were brought up with, the images we see in movies, and from societal constructs.

Someone can have an implicit bias towards any group. You can take the test here: https://implicit.harvard.edu/implicit/takeatest.html

This isn't some made up social justice pseudoscience here. This is pretty widely accepted in the field of psychology and in other social sciences.

Everyone has implicit biases. What matters is that we know about them and understand how to live with them, how not to act on them. We've got to acknowledge our biases so as to make sure they don't become explicit. Even the most progressive individual may have implicit biases, but the important distinction is that they then try to fix it. Racists don't.

Our police, like everyone else, have implicit biases. Studies have shown in video game simulations, they are likelier to shoot an NPC that looks black than white. Perhaps training our police to understand their own biases and to acknowledge them in the field is the next step in law and order reform.