The D.C. Attorney General's Office used invalid alcohol breath test results when bargaining with defendants who then pleaded guilty to driving while intoxicated charges.

For the past year, the city has struggled to get its alcohol breath analysis program in order. In February 2010, it was found that the breath analyzers were producing inaccurate results -- a problem internal police documents suggest could extend back a decade. In March 2010, the District replaced the breath analyzers. The chief toxicologist refused to sign off on their validity, documents show, but the police department continued to use them in the field. The Attorney General's Office stopped using the results as evidence during trial, though continued to use the results during plea bargaining.

"They flat out did it," attorney Bryan Brown told The Washington Examiner. "There could be in excess of 100 cases."

An internal audit conducted by the Attorney General's Office found that between March and September, when prosecutors stopped using the evidence entirely, 11 defendants who were given invalid breath tests chose to plead guilty to DWI. The audit found there was no evidence in those cases suggesting the defendants were otherwise innocent.

At-large D.C. Councilman Phil Mendelson told The Washington Examiner that he wants the Attorney General's Office to be clear about how breath test evidence was used. Mendelson's council committee has oversight over the police department and the Attorney General's Office.

During a hearing Monday, Mendelson quizzed Deputy Attorney General Robert Hildum on the problems in the city's broken alcohol breath test program. Hildum testified that the Attorney General's Office stopped using breath test scores to prosecute drunken-driving cases in February 2010. Hildum later said not using breath analysis scores has not hurt the prosecution of cases.

But for driving while intoxicated charges to stick, prosecutors must present valid scientific evidence -- such as a breath test.

"Are the breath tests and DWI charge still being used, but for the purpose of obtaining a plea rather than a trial?" Mendelson asked Hildum in a letter the councilman sent Wednesday.

Police union chief Kris Baumann said much of the confusion could have been cleared up had a top police official been present at Monday's hearing.

"Mayor Vince Gray promised accountability, and at the first opportunity his administration had to step up and prove it, they didn't do it," Baumann said.