It's not part of a contract, which is binding and enforceable, and which once and while in place, citizens have very restricted ability to change via the political process. It's part of the policy of the existing elected officials, which is very much amenable to public pressure and elections. Given the context of the discussion is whether or not citizens have the power to effect these things through the political process, pointing out this difference is not “nitpicking”, as the difference is on the exact question being discussed.
Examining the problem constructively, then each aspect does have different details to pay attention to. But they also have similar shapes with momentum and indirection. Civil and administrative penalties need to be fixed through the explicit contract, which takes a contract cycle and can be derailed behind the scenes by corrupt officials. Criminal penalties need DAs willing to uphold the law, which takes an election cycle and can be derailed behind the scenes by corrupt officials. Analogously to what you said - once a DA is in place, "citizens have very restricted ability to change via the political process".
The biggest issue is that a small chance of a twenty million dollar payout in case of an egregious murder isn't worrisome to a municipality, and specifically to its politicians who's liability is limited to possibly losing their job. Meanwhile if they do advocate for reigning in the police, the union will most certainly make them lose their job at the next election. So while we can talk about municipalities being responsible for the paramilitary forces they're creating in the abstract, this is clearly not an effective mechanism for reigning them in.