What's on the mind of a police officer when he or she pulls someone over on suspicion of drunk driving? If it's a desire to meet some kind of enforcement quota, that can be a problem — but one that can be remedied without endangering the public.

A sergeant who tells the New Year's Eve shift to be extra vigilant against intoxicated motorists should be commended. But a supervisor who announces that every officer should ticket x number of drivers each week or face demotion has likely violated a 2006 state law that bans quotas on arrests or citations.

The difference between the two instructions is not always so clear, but it's the crux of the issue in Howard County where District Court Judge Sue-Ellen Hantman last week threw out a case against an Ellicott City woman arrested for driving under the influence.

That decision has incensed Howard County Police Chief William J. McMahon, who claims his department has never used quotas and says they were raised as a defense in this particular case only because of one errant communication. The since-revised internal memo described a federal grant to the county to crack down on drunk and aggressive drivers as requiring 2-4 traffic citations of some type (not necessarily drunk driving) be written per hour by officers.

Such wording is, admittedly, problematic. It's clearly illegal when officers are presented with some kind of reward for meeting them — a bonus or commendation in their employee evaluations, for example. But a federal grant to an agency to allow "saturation" patrolling a certain number of evenings per year isn't the same thing as a direct payment to the officer, or even a favorable review.

To pull someone over on suspicion of drunk driving requires probable cause. The possibility of a quota doesn't change that. In this case, the 22-year-old defendant was stopped because a radar gun caught her going 13 miles per hour above the speed limit on Ellicott City's crowded Main Street. After failing a field sobriety test, a subsequent Breathalyzer test showed her blood alcohol level to be .17 percent, or twice the legal limit.

In other words, the woman's guilt doesn't appear to be a close call, nor does it appear to have resulted from anything beyond standard police work. Speeding justified the stop. Her whopping .17 result justified the citation. Why does the language of one particular memo change any of that? This isn't the same as an illegal search or a coerced confession that provided the crucial evidence that lead to an arrest. The officer on routine traffic patrol merely exercised good judgment in every step of the process.

The police department probably deserves a bit of scolding for the language of the memo. But releasing a criminal defendant with a .17 blood alcohol level because of some internal paperwork having to deal with a relatively minor and recurring federal grant, the wording of which is now disavowed? Sorry, but Judge Hantman went too far.

What if Howard County had received a federal grant to lower homicides that measured performance by the number of arrests? Would the judge have required all the accused murderers to be released at trial? Probably not. Surely, the existence of a grant, with or without some statistical performance measure, would be regarded as trivial.

Drunk driving is a crime that should be treated just as seriously. As a former assistant state's attorney, Ms. Hantman should have known better. Yet, too often, Maryland judges seem to be reluctant to enforce DWI laws — witness how rarely they've required anyone but the most serial of offenders to have ignition interlock devices installed in their cars in past years.

And by the way, Maryland law doesn't say police departments can never use arrests or citation statistics as a management tool, only that there must not be an explicitly use quotas as the "sole or primary criterion for promotion, demotion, dismissal, or transfer of the officer."

Do we want police officers held to quotas? No. People won't trust police officers to make good decisions if they think they're motivated by personal gain. But that doesn't seem to have happened here, and the behavior certainly doesn't justify endangering the defendant and the community with the real possibility there will be more drunk driving episodes in the future — which is exactly what happened when the case was dismissed.