D.C. Police Chief Cathy Lanier exercises a great deal of discretion when it comes to reprimanding officers under her command. But that discretion is not absolute. Under District law, the independent Office of Police Complaints has the final word on whether a citizen complaint results in disciplinary action.

Chief Lanier has refused to accept the OPC's decisions in at least three police misconduct cases since 2010, substituting her own judgment for that of the mayor-appointed panel. By doing so, she is undermining a critical safeguard designed to protect the rights of District citizens who have legitimate complaints against the police, as well as to protect her own officers from unfounded accusations.

Like all police departments, the Metropolitan Police Department has its own Internal Affairs Bureau that investigates allegations of improper use of force or other unacceptable behaviors. But like other professionals, such as lawyers and doctors, police officers often find it difficult to punish their own colleagues.

That's why, in 2001, the D.C. Council gave the civilian-run OPC the last word, reassuring city residents that complaints against police officers will be heard by unbiased investigators outside the MPD. There is no doubt the community views the OPC as an important resource. In January, it logged its 10,000th citizen contact and 5,000th formal complaint since it was established.

According to the OPC's 2012 annual report, 574 complaints were filed last year, a 3.6 percent increase over 2011. Of those, 335 cases were found to have enough merit to warrant a full investigation by OPC staff, resulting in 12 adjudications, no firings, the suspension of two officers and various lesser reprimands for 10 others.

Since the vast majority of the accusations were cleared, Lanier's intransigence is all the more difficult to understand. The public's perception that somebody is "policing the police" is essential to community engagement with law enforcement, which happens to be the cornerstone of her crime-fighting philosophy.

Chief Lanier is asking D.C. Attorney General Irvin Nathan for "clarification" on whether she is required to punish officers that the OPC concludes have stepped over the line. But the law clearly states that the OPC's final decisions "shall be binding on the subject police officer or officers and on the police chief." What is there about "shall" and "binding" that the chief doesn't understand?

"My concern is that it will undermine public confidence in the police department," OPC Executive Director Philip Eure told The Washington Examiner. That should be the mayor's and the council's concern, as well.