The Brennan Center for Justice’s latest publication, “Federal Prosecution for the 21^st Century,” focuses on success measures for federal prosecutors and suggests ways for the 94 US Attorneys’ Offices to reorient themselves toward the “twin goals of reducing crime and reducing mass incarceration.”

The report, along with the news that Attorney General Eric Holder is stepping down, is sparking a much-needed conversation about what will be required from federal prosecutors to further reduce the federal prison population. While recent changes at the Department of Justice represent a sea change at the federal level, state prosecutors play a disproportionately large role in driving mass incarceration.

Here are 10 reasons why your local district attorney race is just as important to reducing national prison growth as the fight over Holder’s successor.

1. Eighty-six percent of the national prison population is under the jurisdiction of the states. At the end of last year, 215,866 prisoners were held in federal facilities; 1,358,875 prisoners were under state jurisdiction.
2. All individuals sentenced to state prison have been charged and prosecuted at the local level. While criminal sentences are determined by state legislatures, meting out punishment to those who break the law is the responsibility of the 2,330 state prosecutor offices and the publicly elected county prosecutors and district attorneys who lead them.
3. Local practice can have a profound impact on the state prison population. Between 2000 and 2009, the New York State prison population declined by 17 percent. This decline has been attributed almost exclusively to changes in law enforcement practices in New York City. In fact, prison admissions from counties outside New York City actually increased during this period of reduced imprisonment. But the number of people sentenced to state prison from New York City started declining as a result of fewer felony arrests and convictions.
4. Prosecutorial decisionmaking, in particular, is a key driver of state prison population growth. Local prosecutors have unfettered discretion over whom to charge and what charges to file. Crime rates have steadily declined since 1991, and there has been almost no change in the rate of arrests per crime for decades. But the total number of cases filed in state court rose significantly between 1994 and 2008: in 34 states with available data, filings grew by 37.4 percent. This increase occurred while arrest rates fell by 10 percent.   
5. So-called “tough on crime” policies allow prosecutors to wield tremendous power within the criminal justice system. Mandatory minimums, truth-in-sentencing, three-strike laws, and other penalty enhancements have given prosecutors a wide range of tools with which to punish lawbreakers—and enormous leverage to secure long prison sentences.
6. Prosecutors—not juries or judges—determine guilt in the vast majority of felony cases. In 2009, 98 percent of felony convictions in the 75 largest US counties resulted from plea agreements. Only 2 percent of felony defendants went to trial. With the threat of harsher sentences at their disposal, prosecutors can discourage defendants from having their day in court.
7. Perverse financial incentives tilt the scales of justice toward harsher punishments. Felony convictions that result in a prison sentence are funded by the state budget, while misdemeanor convictions that result in jail time are funded by county budgets. This provides an incentive for prosecutors to “upcharge” less serious crimes to avoid placing the financial burden on sheriffs and other local criminal justice stakeholders. Policymakers in California are trying to alter these incentives with Public Safety Realignment (AB 109), which shifts responsibility for the detention and supervision of nonviolent, non-serious, and non-sex offenders from the state to local governments.
8. Broad criminal laws allow prosecutors to circumvent legislative changes aimed at curbing incarceration rates. In California, early research on the impact of Realignment suggests that prosecutors are already adjusting their charging practices. With more than 30 states passing sentencing reforms to their drug laws in recent years, more research is needed on how prosecutorial decisionmaking changes in response to legislation aimed at reducing imprisonment.
9. The power to determine who goes to prison, and for how long, is largely unchecked by voters and the other branches of government. More than 95 percent of prosecutors who seek reelection win and incumbent prosecutors run unopposed 85 percent of the time. While St. Louis County Prosecuting Attorney Robert McCulloch has received a litany of criticism for his handling of the Michael Brown shooting, he’s running unopposed this November.
10. Prosecutors don’t agree on the objectives that define their success. A 2012 Vera Institute of Justice study found that prosecutors in two New York counties had widely divergent views with respect to charging philosophies, plea bargaining strategies, and the goals of the criminal justice system. The study also found that county prosecutors had very few formal rules or guidelines on how to handle cases. As critical actors that shape the way our society doles out justice, individual prosecutors should have clear guidance on how to measure their performance.

Prosecutors are public officials with tremendous influence and deserve the same scrutiny that is applied to legislators, governors, and other important decisionmakers. Unfortunately, prosecutorial decisionmaking is largely a “black box,” making it difficult for researchers and the public to assess how prosecutorial discretion affects justice system outcomes.

Prosecutors play a critical role in protecting the public. But states have also shown that it is possible to have less crime and less incarceration. We will be hard pressed to accomplish the goal of ending mass incarceration without changes to prosecutorial practice.

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Courthouse photo by Flickr user Jimmy Emerson, DVM (CC BY-NC-ND 2.0)