Decimal Point Error May Invalidate Spokane Washington Breathalyzer Results
The Seattle Post-Intelligencer reports that prosecutors in Spokane, Washington are playing down the significance of improper Breathalyzer calculations, leading to hundreds of faulty alcohol test readings.
The State Crime Lab in Cheney, Washington recently announced that it had been using an erroneous spreadsheet formula to record lab test results for 584 defendants between February 2006 and January 2007. The lab said eight defendants who were harmed by the error have notified.
The Post-Intelligencer reports that a BAC of 0.79 would be elevated to 0.08 percent and 0.149 would read as 0.15. The Director of the Washington State Patrol Forensic Laboratory Services Bureau, Dr. Barry Logan, said 584 cases involved faulty test results, but 576 of the results could not have effected a defendant’s guilt or punishment.
The story appears to allege that the lab’s spreadsheet only showed Breathalyzer results to two decimal places. I tested Microsoft Excel. Breath alcohol level (BAC) results from 0.075 and 0.084 would all show as 0.08 percent, equal to the presumptive BAC level in all states. BAC results from 0.145 to 0.154 would show as 0.15 percent, requiring stiffer penalties under Washington’s excessive DUI law.
KNDO Television said Logan explained that the miscalculations occurred after software used to calibrate breath alcohol instruments was amended late in 2005 produced an error at the fourth decimal place in test readings. Can this be right? An error in the fourth decimal place would not effect a value to only two decimal places.
My simple test, in Excel, showed that either the reporting was simplistic or many more cases should be re-examined.