Sunday, August 15, 2010

Datamaster calibration errors in Alaska

SITTWE MYANMAR - MAY 4:  At the malaria lab, t...Image by Getty Images via @daylifeAlaska now joins the ranks of municipalities investigating errors in calculating BAC levels in suspects charged with DUI. As we've discussed in the past, other states include Pennsylvania, Colorado, California, and Indiana. In Alaska, it recently came to light that the Datamasters used to conduct BAC testing in over 2500 cases over the last few years were calibrated improperly. The specific problem is explained in this Anchorage Daily News article as follows:
The problem involves dry gas tanks, also known as “alco bottles,” used in confirming the accuracy of the DataMaster instruments, which drunken-driving suspects blow into to determine breath-alcohol content. The tanks contain a known sample of alcohol that the instrument measures before and after every test to ensure it is functioning properly. When the state crime lab prepares the bottles, the alcohol levels are measured 10 times and the results are entered into a spreadsheet, which calculates the average value. Because air pressure can affect the test results, the average value is then adjusted to a standard barometric pressure from what it was on the day the tank was tested. But back on Feb. 16, 2006, a trainee and an analyst thought the correction factor didn’t appear right and decided to invert the fraction, said Orin Dym, director of the crime lab. And because it was in a spreadsheet that calculated the values automatically, no one noticed until Dec. 8, 2009... By the time the error was discovered, 48 of the 663 tanks prepared in the years involved had been affected, according to the state. That means 2,465 tests were conducted with equipment that was prepared with the inverted fraction and that had been corrected for the barometric pressure in the wrong direction, according to the Department of Public Safety.
The state concedes that the equipment was tested using flawed quality control standards, but claims that the error didn't affect the actual BAC testing--instead, it allegedly impacted only the quality control checks that accompany each test. According to the State, only 2 DUI cases were affected by the error. Alaska criminal defense attorneys aren't buying that theory and at least one is already moving forward with challenging his client's DUI conviction. The Alaska calibration error is just one more example of how tenuous and error-prone the process of measuring blood alcohol levels can be. People's liberty lies in the balance--and in many cases, faulty lab test results or improperly calibrated breath test equipment is the deciding factor. Visit Americas Top DUI and DWI Attorneys at or call 1-800-DIAL-DUI to find a DUI OUI DWI Attorney Lawyer Now!
Enhanced by Zemanta

No comments: