What to Know: Prosecutorial Misconduct and the Death Penalty

DPI’s ​“What to Know” series exam­ines cap­i­tal pun­ish­ment from mul­ti­ple angles, one top­ic at a time. Each install­ment pro­vides essen­tial facts and data on spe­cif­ic aspects of the death penalty.

Why it mat­ters: More than 600 cap­i­tal con­vic­tions or death sen­tences have been over­turned or led to exon­er­a­tions because of pros­e­cu­to­r­i­al mis­con­duct, and researchers say the true scope of the prob­lem is like­ly far greater.

• DPI has iden­ti­fied more than 600 instances in which a cap­i­tal con­vic­tion or death sen­tence has been over­turned or a death-sen­tenced pris­on­er was wrong­ful­ly con­vict­ed as a result of prosecutorial misconduct.
• More than 6.3% of all death sen­tences imposed since 1972 were reversed because of pros­e­cu­to­r­i­al mis­con­duct or result­ed in an exoneration.
• Of the 202 total death row exon­er­a­tions, at least 144, or rough­ly 70%, involved pros­e­cu­to­r­i­al mis­con­duct specif­i­cal­ly (a sub­set of the broad­er ​“offi­cial mis­con­duct” cat­e­go­ry, which also includes police and oth­er government misconduct).
• The most com­mon types of mis­con­duct were with­hold­ing favor­able evi­dence, impli­cat­ed in 35% of reversed con­vic­tions or sen­tences, and improp­er argu­ment, present in 33% of reversed sentences.
• A report by Harvard Law School’s Fair Punishment Project found that just five pros­e­cu­tors with high rates of mis­con­duct are respon­si­ble for more than 440 death sentences.

Key Facts

• Prosecutorial mis­con­duct is rarely pun­ished. Many instances of mis­con­duct go unad­dressed, and most pros­e­cu­tors who com­mit mis­con­duct are not held accountable.
• Courts fre­quent­ly deny relief even when mis­con­duct is proven, dis­miss­ing it as ​“harm­less error.” DPI’s doc­u­ment­ed mis­con­duct dataset reflects only cas­es where courts con­clud­ed that vio­la­tions were seri­ous enough to warrant reversal.
• Evidence sup­pres­sion is the most com­mon form of mis­con­duct. Under the 1963 U.S. Supreme Court rul­ing in Brady v. Maryland, pros­e­cu­tors have a con­sti­tu­tion­al duty to turn over all evi­dence favor­able to the defense. DPI’s Prosecutorial Accountability project lists more than 200 cap­i­tal con­vic­tions or death sen­tences that have been reversed based on pros­e­cu­tors’ fail­ure to dis­close excul­pa­to­ry evi­dence. A study in the Journal of Criminal Law and Criminology found that courts found Brady vio­la­tions in 10% of cas­es reviewed, and pros­e­cu­tors ​“were almost nev­er referred to the Bar for discipline.”
• Racial dis­par­i­ties com­pound the prob­lem. Prosecutorial mis­con­duct can include the ille­gal exclu­sion of peo­ple of col­or from juries, in vio­la­tion of Batson v. Kentucky. All-white and near­ly all-white juries have been found to be more con­vic­tion-prone and more like­ly to impose death sen­tences. A 2020 report by the National Registry of Exonerations found that police or pros­e­cu­to­r­i­al mis­con­duct occurs more fre­quent­ly when the defen­dant is a Black person.
• Misconduct pro­longs wrong­ful impris­on­ment. Exonerations take longer in cas­es involv­ing offi­cial mis­con­duct because of ongo­ing efforts by gov­ern­ment offi­cials to hide mis­con­duct and false tes­ti­mo­ny or accu­sa­tions. Prosecutorial offices also tend to more aggres­sive­ly defend cas­es and legal claims in which offi­cial mis­con­duct is charged. Official mis­con­duct was present in all eight of the cas­es in which an exon­er­a­tion occurred 31 or more years after conviction.
• The prob­lem isn’t lim­it­ed to cap­i­tal cas­es. Official mis­con­duct was the lead­ing cause of wrong­ful con­vic­tions in 2024, present in at least 104 exon­er­a­tions, or rough­ly 71% of all exon­er­a­tions dur­ing the year. Misconduct con­tributed to wrong­ful con­vic­tions in about 79% of homicide exonerations.

Current Developments

On May 28, 2026, the U.S. Supreme Court ruled 5 – 4 in favor of Mississippi death-sen­tenced pris­on­er Terry Pitchford, find­ing that his con­sti­tu­tion­al rights were vio­lat­ed when a pros­e­cu­tor used peremp­to­ry strikes to exclude four Black prospec­tive jurors and the tri­al court failed to allow him to rebut the pros­e­cu­tor’s stat­ed race-neu­tral jus­ti­fi­ca­tions. Writing for the major­i­ty, Justice Brett Kavanaugh found that ​“things broke down” dur­ing jury selec­tion and that the Mississippi Supreme Court’s con­clu­sion that Mr. Pitchford had waived his Batson chal­lenge was unrea­son­able. At the cen­ter of Mr. Pitchford’s case is retired District Attorney Doug Evans, the same pros­e­cu­tor whose repeat­ed, race-based mis­con­duct led the Supreme Court to vacate the con­vic­tion and death sen­tence of Curtis Flowers in 2019. Mr. Flowers was lat­er ful­ly exon­er­at­ed. Both these cas­es illus­trate how a sin­gle pros­e­cu­tor’s pat­tern of mis­con­duct can affect mul­ti­ple defen­dants across decades.

In 2024, a fed­er­al judge ordered Alameda County District Attorney Pamela Price to review 35 active death penal­ty cas­es after hand­writ­ten notes from a 1990s cap­i­tal tri­al revealed that pros­e­cu­tors in Alameda County, California, had sys­tem­at­i­cal­ly exclud­ed Black and Jewish peo­ple from par­tic­i­pat­ing as jurors on cap­i­tal cas­es dat­ing as far back as 1977. U.S. District Court Judge Vince Chhabria wrote that the notes ​“con­sti­tute strong evi­dence that, in pri­or decades, pros­e­cu­tors from the office were engaged in a pat­tern of seri­ous mis­con­duct, auto­mat­i­cal­ly exclud­ing Jewish and African American jurors in death penal­ty cas­es.” District Attorney Price said that the behav­ior was ​“not lim­it­ed to one or two pros­e­cu­tors” but involved ​“a vari­ety of pros­e­cu­tors” across the office.

Context/​Global Perspective

The prob­lem of unchecked pros­e­cu­to­r­i­al pow­er in cap­i­tal cas­es is large­ly unique to the United States. Most peer democ­ra­cies have abol­ished the death penal­ty, while the United States con­tin­ues to rely on a decen­tral­ized crim­i­nal jus­tice sys­tem in which local pros­e­cu­tors exer­cise broad dis­cre­tion over charg­ing deci­sions and whether to seek a death sen­tence. Unlike many coun­tries where pros­e­cu­tors are appoint­ed through cen­tral­ized nation­al sys­tems, most American pros­e­cu­tors are elect­ed offi­cials who must respond to local polit­i­cal pres­sures and vot­er pref­er­ences. Research has found that elect­ed chief pros­e­cu­tors can sig­nif­i­cant­ly influ­ence the puni­tive­ness of local court sys­tems, illus­trat­ing the sub­stan­tial pow­er these offi­cials wield over criminal outcomes.