Regular readers of this blog know that we hold a rather jaundiced view of field sobriety tests. Police tend to rely on them a lot when deciding whether to press ahead on an arrest for suspected driving under the influence. What they don't tell you is that the margins of error on such tests are very wide, which makes them a questionable foundation upon which to buid a case.
There are many reasons why it's valid to question the accuracy of the tests authorities use to determine if a person may be driving impaired. Breath tests can be wrong if administered incorrectly or if the measuring device is improperly calibrated. Field sobriety tests are often a weak basis for bringing impaired driving charges, too, because even a sober person can get tripped up by them.
Last week we made note of the fact that a mistake by a Tennessee Bureau of Investigation lab agent is raising serious questions about the integrity of any evidence he may have been responsible for. This week we have more specific information about what could be at stake.