In Wyoming, there are three body fluids tested for blood alcohol content (BAC): blood, breath, or urine. And Wyo. Stat. Ann. § 31-6-105 governs the proper testing methods for these excretions. At bottom, this statute demands that the test be performed “according to methods approved by the department of health and by an individual possessing a valid permit to conduct the analysis.” So, there are protocols in place, but what actually happens?
For a breath test, a roadside portable breath test (PBT) is not going to cut it. PBTs are notoriously inaccurate though they are good for determine the yes/no question of is alcohol present in this person’s system? Basically, good for prom; bad in court.
So, most responsible officers will not rely solely on the PBT results, but will, if the person is compliant and willing to submit a breath sample, use a “desktop stationary breath tester” located at the jail or police station. There, the officer will check the person’s mouth for foreign objects like chewing tobacco, dentures, food, drink, and the like and observe the person for 15 minutes before obtaining a sample of their breath. The officer will then wait another 10 to 15 minutes and take a second breath sample. The rationale for two samples is that a breath BAC result can vary slightly with the desktop testers and there is substantial evidentiary value in having a two results to determine with more certainty the person’s BAC.
Now, desktop breath testers are not necessarily the paragon of accuracy either. A 2019 New York Times report found that the mechanical operation and computer programming inside desktop breath testers are shrouded in secrecy and, upon scrutiny, revealed numerous programming errors, design defects, user errors, quality control errors, and so on. And these issues were not without consequence, as the report stated:
The other primary method of obtaining a person’s BAC is with a test of a sample of their blood. This process is the most accurate method of the options available, but it takes some time as the blood must be drawn, packaged, and shipped off to the Division of Criminal Investigation’s (DCI) lab for analysis. It can take about 2 to 3 months from the date of the blood draw to the time the results are shared with law enforcement, prosecutors, and defense counsel.
The process looks like this: the person is transported to a detention center with a duly licensed nurse or phlebotomist or a hospital with qualified personnel. The medical professional draws two samples of the person’s blood using a designated blood draw kit provided by law enforcement. The medical professional initials the vials and marks the date and time of the draw. The samples are sealed in the kit with tape that is marked and initialed by law enforcement. Law enforcement stores the kit and the samples until they can be shipped to the lab for testing. The lab will then confirm the identifying details on the kit before analyzing the samples for BAC. Once the analysis is complete, the lab will return the samples to law enforcement who will store them until trial. In some instances, the lab will hold onto the samples.
(Note: if a person contests that the blood sample(s) analyzed really belong to him or her, the person has the right to test the samples at an independent lab for review of who they came from. The cost for these independent tests is around $2000-$3000.)
The test results from the lab will be documented in a “report” that provides the BAC determination.