That's how you lose Police Officers. Workers prefer to work in safer jobs, and are even willing to take pay-cuts to work in a safer area.
A US-police department is in constant competition with rival cities for the same pool of applicants. If your local police department gets a reputation of not backing its officers, your officers will LEAVE to other cities. Period.
There's a reason why all cities back their Police Departments with as much support as possible. Its a necessary part of attracting the best candidates. Some Police Officers have degrees in criminal law theory, college-educated. Other police officers are just high-school graduates with some muscle.
When police departments struggle, they lose the higher-quality officers to their local rivals. Which means either fewer officers, or being forced to hire low-quality officers.
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The fundamental issue here is that Police Departments are too small, making the politics of "local rivals" a toxic culture. Police departments need to be forced to merge together and cover larger areas.
A nation-wide police force would probably be too big, but we can start by eradicating all town-level police forces (less than 20,000 citizens) and merging them into a larger regional area. As long as there are Police Departments that only protect $1-Million homes (where virtually no crimes are committed), you'll have the quality Police Officers leaving the dangerous areas where they're needed (ie: typical inner cities) and working to move towards the richer areas.
You gotta fix the fundamental politics: the underlying driver of the culture.