Who suffers when prosecutors blind justice?

MEAN JUSTICE: A TOWN'S TERROR, A PROSECUTOR'S POWER, A BETRAYAL OF INNOCENCE By Edward Humes Simon & Schuster 492 pp., $26

A recurrent concern with recent efforts to impeach President Clinton is the potential for abuse of prosecutorial discretion. In his closing argument to the Senate, former Sen. Dale Bumpers noted that the testimony of Monica Lewinsky on the critical issue of whether she thought the president had encouraged her to lie was misrepresented in the report of the House Judiciary Committee to the House. When this mistake persisted in the brief submitted to the Senate by the House managers, was this mistake itself perjury?

"Of course not," replied the senator to his rhetorical question. "But I'll tell you what it is: a prosecutor wanting to win too badly."

What if the target of a criminal investigation is not as powerful as Mr. Clinton? With obvious exceptions such as the O.J. Simpson case, ordinary crimes in the county courts of America are reported but rarely analyzed carefully by the news media. Still less attention is paid to the role of the prosecutor, who for good or ill is the most powerful figure in the criminal-justice system.

In "Mean Justice," Edward Humes, winner of a Pulitzer Prize for investigative reporting, probes what can go wrong when a prosecutor wants to win too badly.

The bulk of the book is a case study of a defendant now serving a sentence of life without parole in a California prison for the murder of his wife for financial gain. Humes says that this prisoner, a retired high-school principal named Pat Dunn, is innocent. He amasses enough evidence in his book - based on the trial record and the files of Dunn's private investigator - to cast substantial doubt on the legitimacy of Dunn's conviction.

A homicide can be proved beyond a reasonable doubt without locating the body, let alone the murder weapon or an unassailable eyewitness to the event. In Dunn's case the body of his wife was found weeks after she had disappeared, but an exhaustive search of the Dunns' home and cars, accompanied by a 15-hour interrogation without Miranda warnings, did not turn up the weapon or a shred of physical evidence linking the husband to the crime. Once the homicide detective decided Dunn was the murderer, he looked nowhere else.

Prosecutors have a constitutional duty to disclose to the defense all information that would tend to prove the innocence of the accused, or at least cast doubt upon his guilt. In his gripping tale of official corruption, Humes demonstrates that prosecutors in Bakersfield, Calif., have repeatedly violated this cardinal rule of our justice system not just in the Dunn case, but in a series of egregious episodes going back to the 1980s.

Sadly, there is no meaningful supervision or sanction for prosecutorial misconduct of this sort. Humes shows that these abuses are occurring not only in Bakersfield, but in many communities throughout the land. In most instances, of course, they go unreported.

Justice William Douglas once wrote that the function of the prosecutor "is not to tack as many skins of victims as possible to the wall, [but] to vindicate the right of the people as expressed in the law and give those accused of crime a fair trial." This sensible view of the prosecutorial function is shared by tough law-and-order judges appointed by Presidents Reagan and Bush, whom Humes cites to the same effect.

We should read this book and weep for all who have lost their liberty or even their life because of a prosecutor who wanted to win too badly. Better yet, would be to get involved in efforts to reverse the trend denying meaningful post-conviction relief to prisoners wrongly convicted, and to impose serious consequences on law-breaking officials.

Our streets are not safer when innocent people are behind bars or executed for crimes they never committed.

*Edward McGlynn Gaffney Jr. is a professor of law at Valparaiso University.