Recent debate over policing and justice has brought new attention to an old question. How should the personal and employment histories of law enforcement personnel matter to a criminal case?

Many argue that juries and district attorneys should be able to know if arresting officers, interrogators or evidence labs have a history of lying, abuse, incompetence or corruption. Others doubt whether reaching this admirable goal would or could be done fairly and in the public interest.

The long-standing Brady rule demands police openness

In 1963, the U.S. Supreme Court created the “Brady rule” that people accused of crimes have a constitutional right to see all “materially exculpatory” evidence police and prosecutors have.

If the information would make the accused seem more innocent, reduce their sentence if convicted or change witness credibility in their favor, the government must hand it over to the defense.

In 1985, the court strengthened the Brady rule by clarifying what “materially” exculpatory means. They said that prosecutors must share evidence if concealing it could undermine confidence in a guilty verdict.

The Brady rule often treated as a suggestion

Nevertheless, police personnel records that might favor the accused are not always easy to pry loose, making it tough to follow the Supreme Court’s Brady rule.

This can put voter-elected district attorneys on the spot when juries can’t see the same reports about individual cops that voters can read in the news.

“Brady lists” bring even more heated debate

One solution is to create a so-called “Brady list,” really a database of officers whose evidence may be too vulnerable to challenges to be used in prosecutions. Some argue the Brady rule demands the sharing of such lists with defense attorneys.

Police unions and others counter that confidentiality laws protect officers like any other citizen, and due process should come before being added to a database. Some see the databases as blacklists likely to destroy careers and put officers and their families in danger.

In the meantime, the National Registry of Exonerations has so far tracked about 2,500 exonerations of prisoners who wasted years behind bars before being shown to be innocent and released. Most of the wrongful convictions involved the failure to share evidence of innocence, which violates the Brady rule.