DWI Defense: What is an "Observation Period" and How Does it Affect a DWI Breath Test?
Updated: Jul 18, 2019
Here in Rochester, Minnesota many DWI charges have been dropped due to officers failing to conduct a proper observation period prior to a breath test. Godwin Dold has had multiple DWI charges dropped to mere traffic violations, such as speeding or failure to signal a turn, based on this issue. The interesting part about this challenge is that it has very little to do with that the driver did or didn't do, and instead focuses on whether the police officers strictly followed their training and protocols. Most drivers have no idea this issue even exists until their case is reviewed by a competent DWI defense attorney.
So why is an observation period important? The first thing to understand is the concept of "mouth alcohol," which is alcohol that has traveled from the stomach into a person's mouth, typically through burping or vomiting. When this happens the alcohol will be present in the mouth for a period of up to fifteen minutes. This mouth alcohol will artificially increase an alcohol breath test, causing an inaccurate high result. Put another way: mouth alcohol can cause a result that should be below the legal limit to jump over the legal limit and cost an innocent person their driver's license and lead to criminal charges.
Because such a result is unjust and unfair, the Minnesota Bureau of Criminal Apprehension (BCA) requires every test subject to be observed for fifteen minutes immediately before given a breath test. If the subject burps, belches, or vomits during that time a new observation period is required.
Lately, many officers have forgotten about this requirement or taken shortcuts. We have have seen officers leave subjects alone for many minutes just prior to testing and we even had an officer who completely skipped the observation period altogether.
Many of our clients had never heard of an observation period, so they were thrilled when this issue was brought to their attention and our motions to throw the test results out were granted. This resulted in their getting their licenses back and their criminal DWI charges dropped.