The following editorial appeared in the Los Angeles Times on Tuesday, April 2:

In its landmark 1963 decision in Brady v. Maryland, the U.S. Supreme Court ruled that prosecutors are required to provide defendants with any information that may help prove their innocence or favorably change the outcome of their trials. That decision recognized that an individual’s right to a fair trial is undermined if prosecutors withhold exculpatory evidence.

But half a century later, some prosecutors still don’t get it. In some cases, overzealous district attorneys willfully fail to comply with their Brady obligations, resulting in egregious miscarriages of justice. In other cases, their failure to abide by the Supreme Court’s ruling is more subtle.

For instance, some states have enacted tough-on-crime laws, such as California’s Proposition 115, that have cast doubt on a prosecutor’s responsibility under Brady. Passed in 1990, Proposition 115 put in place broad limitations on defendants’ rights. One of its provisions required prosecutors to turn over potentially favorable evidence to the defense at least 30 days before trial. That allowed some prosecutors to conclude that they did not have to hand over Brady material during preliminary hearings, at which judges consider whether sufficient evidence exists to bring charges against an accused person. Preliminary hearings take place well before the trial itself.

Thankfully, two California appellate courts recently stepped in to clear up any confusion, ruling that a prosecutor’s obligation under Brady does not apply just at trials, but extends to preliminary hearings as well. The two court decisions will help protect both defendants’ constitutional right to due process and the public’s interest in avoiding a waste of scarce public resources.

Preliminary hearings serve an important purpose: They weed out groundless charges that will not withstand scrutiny at trial. That purpose, however, is undercut if prosecutors may arbitrarily decide to withhold exculpatory information from defendants and their attorneys.

Consider the case of Baldomero Gutierrez, a Concord, Calif., man accused of committing lewd acts with his two foster daughters. After a preliminary hearing, Gutierrez was charged based on the testimony of a detective. But it was subsequently learned that the district attorney’s office had failed to inform the defense or the judge that one of the two girls had made false accusations of molestation against another man several years before. The case was eventually dismissed, and the judge ruled that if prosecutors had provided the information earlier, the case never would have gone to trial in the first place.

Lawyers from the Contra Costa district attorney’s office argued that they didn’t have to turn over the exculpatory material at the preliminary hearing because of the 30-day rule in Proposition 115. Now it’s clear that that interpretation is wrong. The reality is that suppressing evidence, even if it is during a preliminary hearing, robs an individual of his constitutional right to due process.

The chief issue here is not the waste of resources involved in holding trials that need not be held. Rather, it is the right of a defendant — innocent until proven guilty — to all the information that might help him rebut the charges brought against him. That is a right guaranteed by the U.S. Constitution and recognized by the Supreme Court in Brady vs. Maryland.

“Contrary to the people’s argument,” wrote Justice Peter J. Siggins of the California 1st District Court of Appeal, “nothing in Proposition 115 could supersede the prosecution’s Brady obligation under the United States Constitution.”

Prosecutors must remember that their mission is to achieve justice and not simply to obtain convictions. Turning over exculpatory evidence to defendants before a preliminary trial is one good way to ensure that goal.