In California, "state prison overcrowding is due in large part to county decisions about how to deal with crime. . . data from 2000-2009 [show that] . . . California’s counties use state prison resources at dramatically different rates, and, moreover, that the counties which use state prisons the most have below-average crime rates. . . . incarceration in state prisons is one policy choice among many, not an inexorable reaction to violent crime.
Counties can and do make different choices about how to respond to violent crime, including the extent to which they use prison. . . . [L]ocalities are crucial - and critically underexamined - contributors to state prison populations. Decisions are made at local levels about prosecution, investigation, plea bargaining, and sentencing, and these decisions are made by officials who are either elected locally (such as DA’s, judges, and sheriffs) or appointed locally (police and probation officers). Local policies and policymakers affect the state’s corrections budget, even though the state has no say in designing or implementing these policies."
From the abstract to "Tough on Crime (on the State's Dime): How Violent Crime Does Not Drive California Counties' Incarceration Rates -- And Why it Should" by W. David Ball.
The notion that criminal justice decisions have budget implications that work like an entitlement program, mandating spending with little regard to the amount appropriated by the state budget for the purpose, is familiar. The notion that local exercises of discretion in the criminal justice system can be as important as the text of the state criminal code in driving incarceration rates is not unfamiliar, if less commonly observed.
But, the notion that disparities in criminal justice discretion are a distributive justice issue between local governments, with excessive incarcerators imposing burdens on other state taxpayers who have no say in those decisions is a conceptual breakthough.
The article linked looks at these issues in California, but they also come up in Colorado, where suburban Denver's Arapahoe County's notorious prosecutor exercises discretion to impose longer and more expensive sentences of similarly situated defendants than prosecutors elsewhere in the state, such as the neighboring urban City and County of Denver. But, I'm not aware of anyone that has done a study looking at the issue from the frame that Ball does in Colorado, even though all or almost all of the relevant data are fairly easily available online in government statistics.
The high sentences sought in Arapahoe County in the criminal justice system impose fiscal burdens on other Colorado taxpayers in a way similar to, but less transparent than the efforts of the exurban Denver area Douglas County school board to unilaterally establish a voucher plan that would give students attending private (mostly religious) schools a partial share of the per student state funding that the district receives (and no local money) if it can succesfully make the case that voucher students count for school funding formula purposes. In other words, both proposals are to a significant extent money grabs at a scarce state general fund by affluent communities led by politicians who have a strong public ideological opposition to taxes and government spending.
Framing sentencing law as a fiscal issue rather than a human rights issue has produced a major withdrawal from war on drugs and tough on crime politics driven long sentences for relatively minor crimes in a variety of conservative leaning political jurisdictions. Perhaps a focus on considering local sentencing discertion in a fiscal frame could elicit further reforms that address abuses of discertion by local political actors in this process, where traditional liberal and academic arguments for sentencing reform have not.