The Floyd protests were based on multiple lies. First, police brutality is not a racial issue. White suspects are actually more likely to face lethal use of force by police than blacks, as shown by Roland Fryer's study.
Another lie was that Floyd suffocated from a knee to the neck. He had been suffering from a drug overdose and complained of breathing difficulties before that technique was applied. Most of the reason for Chauvin's conviction came down to jury intimidation that was enabled in part by the media not being discreet with juror details and by legitimate fears by the jurors of what would happen if conviction didn't happen.
Of course, that case is far from being the only racially charged case with jury intimidation.