Cops can ignore Black Lives Matter protesters. They can’t ignore their insurers

In the US, the insurance industry has essentially driven building and construction safety for more than a century. For example electrical devices are required by building codes to be listed and Underwriter's Laboratories [UL] is one of the most common listings. Even further, local governments frequently build new fire stations in order to secure insurance rate reductions for local industrial uses. Historically, the National Fire Protection Association [NFPA] was organized by insurers and created requirements for fire sprinklering risky occupancies [where "risky" is to a non-obvious degree about the fire hazard a building imposes on neighboring buildings].

Anyway and although I am not a lawyer, local governments receive high levels of judicial deference in matters absent clear statutory requirements particularly in matters of staffing under the tautology that government make decisions based on politics. Without clear regulatory guidance such as state or Federal employment law, the only place due process would enter the equation is in the form of an individual or collective employment contract.