A Howard County judge threw out charges Thursday that an Ellicott City woman was driving under the influence of alcohol, ruling that they were linked to an illegal quota indicating that officers had to cite two to four motorists every hour.

It was unclear how many other county cases might be affected by the ruling, which involved federally funded initiatives that targeted drunk and aggressive drivers from January through April of 2011. At least two other similar cases are pending before the same judge.

Howard County Police Chief William J. McMahon, in an unusual criticism, called District Judge Sue-Ellen Hantman's decision a "bad ruling" and said an appeal is likely. The police chief said a memo distributed to officers contained, "in retrospect, not the best wording," and conceded that he "could see how it could be misinterpreted."

McMahon added, "We don't have quotas. It's against the law, and it's not how we manage the Police Department."

Motorists pulled over for traffic stops routinely suspect they're victims of a quota system designed to enhance revenue or build an officer's resume, or both. That perception has been stoked occasionally by leaked memos or emails that supervisors send out to implore officers to work hard.

But this is the first time lawyers and police can recall that a judge threw out a criminal case based on such a missive. The driver's attorney, Mark Muffoletto, subpoenaed police memos that served as the crux of his case.

Gary McLhinney, an executive with the Fraternal Order of Police, which represents officers in Howard County, said the issue indicates that "there is a problem with what leadership is doing. The rank and file didn't do anything wrong. But they're suffering the consequences."

McLhinney, a former Baltimore police officer and former chief of the Maryland Transportation Authority Police, said, "It introduces an unwanted dynamic in every traffic stop. Citizens are not only upset that they get stopped, but now they can question the motives. People of Howard County need to have the confidence that the police are doing the right things for the right reasons."

In 2006, then-Howard County Police Chief Wayne Livesay canceled a short-lived policy that some officers perceived as a quota. It called on them to make three traffic stops a shift and an average 11/2 drunken-driving arrests each month.

Thursday's case stems from the April 2011 stop of Katie Majorie Quackenbush, 22. Officer Erika Heavner stopped her 2001 Honda on suspicion of driving 38 mph on Ellicott City's Main Street, where the speed limit is 25 mph.

McMahon said the woman's blood alcohol content registered 0.17 percent, more than twice the legal limit, and she was arrested. The officer was working what is called a "saturation patrol" that used overtime funded by a federal grant to target drunk and aggressive drivers.

The police chief said that "we have more deaths in traffic incidents than we do in violent crime" and that every officer is pushing to "do everything we can to stop intoxicated drivers and get them off the road."

Hantman ruled from the bench and did not issue a written opinion. She is a former prosecutor in Howard County, once served as a Democratic Central Committee chairwoman and in 1994 contemplated a run for Howard County executive.

Hantman did not return calls to her chamber seeking comment. Both the defense attorney, Muffoletto, who was in the courtroom, and the police chief, McMahon, confirmed her decision. Electronic court records show that the defendant, Quackenbush, was acquitted of all charges on Thursday. Court records show she faces another speeding case in Howard County, accused of driving 71 mph on U.S. 29.

The quota issue arose from the federal grant, which included ways to measure performance. McMahon said the grant "mandated that an average of 2-4 citations must be written per hour on each of these details by each officer or future funding may be withheld."

McMahon said an employee who administers the traffic safety program repeated that wording on an internal memorandum distributed to officers on the detail. He said there was no intention to set quotas, and noted they are illegal when linked to employee evaluations — by penalizing officers for failing to meet a benchmark, for example.

But McMahon acknowledged that supervisors questioned the memo and it was revised.

"I know there was some concern about the wording," McMahon said. "It was a guideline given to the officers. Grants have expectations, and this was a way of explaining that to the officers. … The goal clearly wasn't to set out for X number of citations. It was a well-intended effort to underscore the importance to be active on these details.

"All funding is scarce. The public has an expectation that we make good use of these funds. … I acknowledge how this could be misinterpreted. That's why we don't use it anymore."

McMahon said it was unfair to judge traffic enforcement efforts by a single instance.

But a December 2010 stat sheet obtained by The Baltimore Sun includes a handwritten notation advising county officers of "a prize" for boosting traffic stops 60 percent. This memo was not used in the court case.

Muffoletto said the practice is more widespread than the traffic stops made under one grant. He called the ruling from a former prosecutor "courageous" and disputed the police chief's explanation.

"It is a quota," he said. "Just because they were caught … doesn't change the fact that it was a quota."

peter.hermann@baltsun.com