In a country with hundreds of millions of people and hundreds of thousands of police, there will be times where an officer shoots and kills a suspect. Systems have been put in place so that the community is allowed to evaluate these incidents. Police departments are also subject to lawsuits and controls by local governments. Now, they get to experience the injustice of social justice.
Let’s say you have a police force and some unarmed Black criminal is shot by a cop. Police are not required to be shot at first, or even see a gun. Sometimes, they are exonerated. Other times, they are found at fault. What happened in Baltimore is that the police were found to be at fault by default. The mayor promised to crack down on abuses by police to prevent the death of a suspect.
In industry, the goal is to have 0 defects and 0 tolerance for error. That is impossible. The closer you get to zero defects and minimal tolerances, more effort, time and money is involved. When it comes to something as human as law enforcement, there is no extra time or money and the effort can only go so far.
The result is that police are being more careful to not get in trouble with the vigilante law. They won’t engage unless the situation is clear, and must act from a position of greater safety because they have little recourse in defending themselves. The result is the increase in the deaths of citizens by other unsavory citizens.
This is more a matter of pragmatism than right and wrong. It is a simple equation. If a population does not respect police, crime goes up. If police are attacked for doing something, even a justified response, they will avoid that response and the public gets in greater danger. If law enforcement as a profession is denigrated, there will be a less qualified pool of applicants. If you fight for a city without law enforcers, you will have a city without law.