LINCOLN, Neb. (AP) — More than 200 drunken driving cases in southeast Nebraska could be affected by a certification issue with some breath tests conducted by law enforcement, according to a county prosecutor.

Certain breath tests are being tossed out as evidence in western Nebraska counties. But a judge hasn’t ruled on the issue in Lancaster County courts yet, according to local attorneys.

“We intend to go forward with the prosecutions and look at each case,” said Lancaster County Attorney Pat Condon.

State regulations require a simulator solution be used to regularly test the accuracy of each breath-test machine’s readings. The solution must come with a certificate of analysis and a signature of the person responsible.

A Gering attorney discovered earlier this month that the person who signed off on the tests never actually conducted them. Many DUI cases depend on evidence from breath tests taken at jail or detox, which differ from the preliminary tests given by police on the street.

Lincoln defense attorney Mark Rappl has been researching the discovery’s local impact. He believes the certification issues could affect cases dating back more than a year.

Condon and his staff instructed law enforcement to seek only blood samples to establish a driver’s blood-alcohol content until further notice.

If local judges decide to toss out the affected tests as evidence, only some DUI cases will be affected. Prosecutors can still convict drivers who display signs of impairment, including failing sobriety tests, smelling of alcohol or driving poorly.

The certification problem would likely affect aggravated DUI cases, according to Condon. Aggravated DUI cases have stricter penalties and often rely on the level of alcohol in someone’s body.

Rappl said the only thing about drunken driving “that makes it a crime is the number.”