MOUNT VERNON, Wash. (AP) - A hearing continues this week in Mount Vernon that could affect drunken driving cases across Washington.
     
Lawyers started questioning employees of the state toxicology lab yesterday about challenges to the certification and calibration of machines used to test alcohol breath tests.
     
Defense lawyers say the testimony in Skagit County court could affect DUI cases across the state.
     
A State Patrol spokesman, Jeff DeVere, says the patrol is confident in its evidence from drunken driving cases.

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