According to a report in the Detroit News, officials with the Michigan State Police say thousands of blood-alcohol tests may have been incorrectly analyzed. The department's forensic science division told prosecutors that the problem was an "incorrect calibration model" used in approximately 4,001 results over a four-month period.

According to the report, despite the “processing method” problem, half the tests didn't require any correction and the revised results didn't have an impact in cases where the blood-alcohol level was initially found to be near 0.08, the threshold for drunken driving in Michigan. You can read more here.