When Larry Johnson walked out of a Missouri prison during the summer of 2002, exonerated by DNA testing from a wrongful rape conviction after avowing his innocence for 18 years, St. Louis legal community insiders nodded knowingly as word trickled out who had led the prosecution back in 1984—Nels C. Moss Jr.

Moss, assistant circuit attorney for the city of St. Louis and later a trial prosecutor in neighboring St. Charles County, earned a well-deserved reputation as an aggressive, effective trial prosecutor. During his 33 years of trying cases for the people, however, he simultaneously was a recidivist breaker of the rules by which prosecutors are supposed to operate.

After joining the St. Louis city prosecutor's office in 1968, Moss found his conduct formally challenged in at least 24 cases. In seven of those, judges reversed the conviction, declared a mistrial or issued some other ruling adverse to the prosecution.

Over the course of his career as a prosecutor, Moss reneged during trial on a pre-trial stipulation with the defense; called the jury's attention to the defendant's failure to testify, thereby compromising the Fifth Amendment rights of the accused; alluded to the defendant's uncharged criminal conduct, a violation of the rules of evidence; attacked the character of the defendant with information not in the court record; used inadmissible material from a separate trial of an accomplice; promised during jury selection or opening argument to present testimony never offered; attacked the truthfulness of defense counsel; cast aspersions on the integrity of an insanity defense; and inflamed jurors' passions during closing argument.

When one appellate panel reversed a conviction in a case won by Moss, a judge writing a concurring opinion emphasized that the blame lay with the prosecutor and not with the courts:

District Attorney. State's Attorney. Commonwealth's Attorney. County Attorney. Local prosecutors' job titles may differ from state to state, but they all share one basic function: to act as the public's advocate in the resolution of criminal cases.

Prosecutors wield tremendous power. After a suspect is arrested, they act as de facto judge and jury, deciding whether to charge the suspect with a crime, whether to offer a pre-trial deal, and, if so, the terms of the deal. In most jurisdictions, at least 95 percent of the cases that pour in from the police every day never reach a jury. The only trial those defendants receive takes place in the prosecutor's office.

The National District Attorneys Association estimates there are 27,000 local prosecutors in the United States today, spread throughout 2,341 jurisdictions. In many of these, especially the less populous ones, local prosecutors sometimes receive advice, guidance and even courtroom assistance from lawyers in the state attorney general's office. In three states—Delaware, Alaska and Rhode Island— the attorney general is the local prosecutor. When a conviction is appealed, the attorney general's office typically gets involved as a matter of course. So, it is common to hear defense lawyers praise or criticize assistant attorneys general much as they do district attorneys. See the National Association of Attorneys General Web site.

In May 1999, Robert Wasser's life was turned upside down when Walworth County, Wis., Assistant District Attorney Diane Resch charged him with fourth-degree sexual assault. The charge stemmed from a complaint filed by Wasser's then 20-year-old adopted daughter Samantha (not her real name).

Wasser and his wife Bonnie had dedicated their adult lives to helping abused and neglected children. Over the years, the couple had adopted 22 children and were on the state's list of parents who take in special needs kids. The state would sometimes use them for emergency placement when children had nowhere else to go. When the Wassers adopted 14-year-old Samantha, they knew the risks. Her previous foster father had sexually assaulted her, and she would need special care. But they had had success raising similar adopted children and were confident they could help her.

Wasser's troubles began one weekend when Samantha was home from Wisconsin Lutheran College, a four-year, coed liberal arts school in Milwaukee. Wasser found a handwritten note from Samantha to her boyfriend, a man she would later marry, about dropping out of college and leaving Wisconsin together. Wasser confronted Samantha about the note. Later, he drove her back to college.

The drive to Milwaukee was tense—but still, the conflict with Samantha seemed minor to Wasser, considering her painful past. All that changed, however, a few months later, when an overzealous prosecutor with a history of misconduct and a series of mistruths and outright lies turned a minor dispute into a major crisis. While the charges against him were eventually dismissed, he lost his job, his reputation was damaged, and he incurred the expense of a court battle. The woman who prosecuted him, and misled the court in the process, still has her job.

Actual innocence cases in which courts found prosecutorial misconduct

Since 1970, appellate judges ruled on allegations of prosecutorial error or misconduct allegations in 45 San Diego County cases, of which 8 led to reversals, dismissals or acquittals. As in other jurisdictions studied by the Center for Public Integrity, the totals come solely from appellate opinions. San Diego County defense lawyers provided numerous examples of error or misconduct at the pre-trial or trial stage.

But San Diego stands out amidst the 2,341 jurisdictions the Center researched for its attempts over the last 30 years to do things differently—in part because the office of district attorney has been held by prosecutors who have attempted to make the office more accountable. Perhaps a reflection of their success lies in this fact: the citizenry of San Diego County became so educated about prosecutorial misconduct that when it did occur, they were ready to hold the district attorney responsible and vote him out of office, no matter his accomplishments or intentions.

The changes began with the election in 1970 of Edwin L. Miller Jr., who would go on to serve for 24 years. During his tenure, Miller made drastic changes to the office, in part by stressing specialization and career ladders. He encouraged young trial prosecutors who showed talent to stay on permanently, thus solidifying the culture at the top. He introduced some reforms—notably the compilation of an office manual for prosecutors, and the publication of a journal, Law Enforcement Quarterly, first published by the San Diego District Attorney's office in 1971. (Originally a specialized journal for legal professionals, in 1989 it became a more approachable magazine for general readers.)

Unlike any private attorney, the local prosecutor—be he district attorney, county attorney, or criminal district attorney—is an elected official whose office is constitutionally mandated and protected. Prosecutors are still subject to the Rules of Professional Responsibility, but they must police themselves at the trial court level because of their status as independent members of the judicial branch of government. Such a holding is not tantamount to making the fox guardian of the henhouse or letting the wolf keep watch on the flock, because a prosecutor who violates ethical rules is subject to the disciplining authority of the State Bar like any other attorney. Perhaps even more importantly, as mentioned above, his violation of the rules will subject his cases to reversal on appeal when his unprofessional conduct results in a denial of due process to a defendant. Lastly, he, like all elected public officials, must regularly answer to the will of the electorate. Should his conduct create too much appearance of impropriety and public suspicion, he will ultimately answer to the voters. — State ex rel. Eidson v. Edwards, 793 S.W.2d 1 (Tx. 1990)

Prosecutors, like other attorneys, must adhere to the standards of professional conduct that exist in the state where they practice. Every state has a disciplinary system under which lawyers can be punished for violating ethical standards. Some acts of prosecutorial misconduct, apart from leading to reversals of convictions, can constitute ethical violations and thus subject the prosecutor to disciplinary action by the state bar authority.

Jennifer M. Joyce, the current elected circuit attorney in St. Louis, oversees an office whose prosecutors, the Center for Public Integrity found, were challenged at least 167 times for alleged prosecutorial misconduct before she took office. Defendants were acquitted or had their convictions reversed in 29 of those cases. About halfway through her four-year term, Joyce and her staff seem acutely aware of the challenge ahead as they try to improve the situation in their home city.

The task is a daunting one. The top person in the office has a difficult job that tends to become more difficult every decade. That is especially so in major metropolitan areas, where the top prosecutor must manage hundreds of lawyers and support staff with a budget that always seems inadequate, deal with horrific crimes almost every day, think about prevention as well as conviction, all the while balancing the obligation to serve justice with the unavoidable scrutiny of won-lost statistics that become a factor in re-election campaigns. The difficulty has grown in medium-sized and small jurisdictions as well.

Frank Conley, just retired as chief judge of Boone County, Mo., after three decades on the bench, recalled his two terms as the elected prosecuting attorney after his 1962 victory. "In a full eight years as prosecutor, I had two legitimate armed robberies," Conley said. "Now, we have an armed robbery every night. We were just a little town back then." Today, Columbia, the seat of Boone County and its dominant incorporated area, has a population of about 80,000. "Substance abuse and the transient nature of our communities today, where you're here today and gone tomorrow, all of that has contributed to a lot of the problems we've seen," Conley said. "There is no sense of community in the sense that we knew it 30 or 40 or 50 years ago. It is gloomy."

Joyce, whose office is accountable to 333,960 citizens of St. Louis, is well aware of those problems.

For the stories to go along with this project, click here to see the Harmful Error page, or here to read the Methodology behind the data.

While it is not unusual for an amicus curiae brief to be filed in a U.S. Supreme Court case, one such brief, filed on behalf of a Tennessee death row inmate, is unique both for its content and for the men who filed it. Six former Tennessee prosecutors argued, not on behalf of their state or the prosecutor, John Zimmermann, who won the conviction and death sentence against Abu-Ali Abdur'Rahman, but for the defendant. The six made the pattern of behavior of Zimmermann, a prosecutor in Davidson County (Nashville), Tenn., the central issue of their brief.

The U.S. Supreme Court listened to oral arguments in the Abdur'Rahman case in November 2002. Before reaching the highest court, the murder case wound its way through Tennessee's courts during the 1980s, 1990s and into the new century. The defendant in what is arguably Zimmermann's highest-profile case ever was born James Lee Jones. He found himself on death row after being convicted by a jury of murdering a man and wounding his female companion during an armed robbery. The Tennessee Supreme Court upheld the conviction in 1990, despite finding that Zimmermann's conduct in the case had crossed the line. In 1998, a U.S. District Court judge questioned Zimmermann's conduct in the same case, but did not give the defendant his desired result.