Is it possible to rid police officers of bias?

No - because all humans have biases that they learn growing up. People can learn to control those biases and not let them control them. But we're all prejudiced.

It could probably reduce it but never fully get rid of it.

Thats going to be tough, education, training, upbringing, etc PO1 William "Chip" Nagel but things do need to change.

Again and again, when these type of egregious actions occur, it seems the officer had been in trouble time and time again, and yet was still on the force. Your article barely touches on the issue of non-firing of bad officers, however this one from USA Today does. From the article-
"Less than 10% of officers in most police forces get investigated for misconduct. Yet some officers are consistently under investigation. Nearly 2,500 have been investigated on 10 or more charges. Twenty faced 100 or more allegations yet kept their badge for years."
WHEN ARE WE GOING TO STOP LETTING THE POLICE UNIONS AND THEIR ALLIES, THE OTHER PUBLIC SECTOR UNIONS, MAKE IT NEARLY IMPOSSIBLE TO FIRE A BAD COP?

Here's the whole article-
https://www.usatoday.com/in-depth/news/investigations/2019/04/24/usa-today-revealing-misconduct-records-police-cops/ [login to see] /