Legislatures considered 25 witness identification bills in 17 states this year, the National Association of Criminal Defense Lawyers reported. Five states approved bills, while five states defeated them. Bills are pending in seven states.

California's legislature has taken an important step that needs to be ratified by Gov. Schwarzenegger and adopted by other jurisdictions.

The California Legislature also passed a bill this year that requires informant testimony to be corroborated before it can be heard by a jury. Critics say such testimony can be unreliable, especially when it is offered by convicts or suspects in return for leniency. The bill awaits approval by the governor.

States (and the federal government) need to recognize that wrongful convictions are a systemic and all-too-common problem.

Studies of wrongful convictions suggest that there are thousands more innocent people in jails and prisons.

In most of those cases, there isn't DNA evidence available to exonerate the wrongly convicted.

In a 2007 study, Professor Gross analyzed 3,792 death sentences imposed from 1973 to 1989 and found that 86 death row inmates, or 2.3 percent, had been exonerated through 2004. Professor Gross said the total number of innocent prisoners was likely to be far higher. In his view, well-documented wrongful convictions in capital cases provided a window on systemic problems, with even larger numbers of convictions for less serious and less publicized convictions.

Mistakes in the criminal justice system are difficult to rectify. It's better to avoid making them. Although the linked article indicates that some members of the law enforcement community are resisting the kinds of changes that states are being urged to consider, police officers shouldn't complain about rules that are designed to reduce the risk of error. Getting it right is more important than getting a conviction.