How Prosecutors Make Decisions

Published by the national Institute of Justice
Executive Summary 
Prosecuting attorneys enjoy broader discretion in making decisions that
influence criminal case outcomes than any other actors in the American justice
system. They make pivotal decisions throughout the life of a case—from
determining whether to file charges, to crafting plea offers and recommending
sentences. That they do so with little public or judicial scrutiny generates
questions about the justice and fairness of the process.
There is an extensive body of research on factors that affect prosecutorial decision making.
However, this material has several important limitations. First, it focuses
overwhelmingly on quantitative analyses that identify factors having reliable
statistical relationships with case outcomes; few studies have applied
qualitative methods to explore how and when prosecutors’ interpretation of
those factors influence the decision making process. 
Second, few studies are comparative. Some rely on analyses of outcomes in one jurisdiction. 
Others examine one decision point. Still others focus on one offense type.
These studies have found case outcomes to be primarily associated with the strength
of evidence, the seriousness of offenses, and the culpability of defendants.
However, there is scant research on contextual factors that may influence prosecutorial
decisions, such as prosecutors’ characteristics, organizational constraints,
and social context (relationships among participants in the courtroom
workgroup, for example).
Finally, there has been little research examining the influence of prosecutors’ 
conceptions of justice and fairness—how much, for
example, case-level decisions are influenced by the system-level pursuit of
procedural or distributive justice, or by prosecutors’ concerns about the
consequences of their decisions for individual victims and defendants.
With support from the National Institute of Justice, the Vera Institute of Justice undertook
research to better understand how prosecutors make decisions throughout the
processing of a case. The study used data from two moderately large county
prosecutors’ offices, selected because of previous working relationships with
the Vera Institute. The participating counties—identified in the report as
Northern County and Southern County—are roughly comparable in size and
demographics, with just under a million residents each and recent increases in
their Latino populations. Both offices operate in states with determinate
sentencing structures (no discretionary parole), mandatory periods of
post-release supervision, and statutorily defined sentencing guidelines based
on seriousness of the conviction offense and either prior conviction history or
a broad evaluation of risk to the community.8 The guidelines are mandatory in
Southern County but only advisory in Northern County.
Vera researchers examined initial case screening and charging decisions, plea
offers, sentence recommendations, and post-filing dismissals for multiple
offense types in each of the two participating jurisdictions. At each decision
point, they analyzed the impact of legal, quasi-legal, and extra-legal factors
on case outcomes and examined how prosecutors weighed these factors in their
decision making. The research was guided by the following questions:
1. How did prosecutors define and apply the concepts of justice and fairness?
2. What factors were associated with prosecutorial outcomes at each stage?
3. How did prosecutors interpret and weigh different case-specific factors in making
decisions at each stage?
4. How did contextual factors constrain or regulate prosecutorial decision making? This
document is a research report submitted to the U.S. Department of Justice. This
report has not been published by the Department. Opinions or points of view expressed are those of
the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of
Justice.
5. How consistent were prosecutors’ decisions across similar cases? What case-level
and contextual factors influenced the degree of consistency?
Read The entire Executive Summary