The problem is not that police arrest too many criminals, or that they approach their job too strategically by using "predictive policing software," which BLM curiously wants abolished. The problem is not that suspects are required to post bail as a condition of release pending trial, which BLM also wants scrapped.
The answer to both crime and to those occasions when police step out of line is to strengthen the rule of law, not to weaken it. Black Lives Matter is not seeking arrangements that would improve the condition of black people. It is seeking to undermine and weaken a system which, though badly in need of reform, remains the best hope for protecting a minority community whose members are disproportionately the victims of crime, not just its perpetrators.