Updated on February 5th, 2024 at 08:51 pm

 Fighting Wisconsin DUI Blood Tests

Question: Why should I fight my DUI? My blood sample came back over the legal limit.

Answer: Your test result is reported on a piece of paper, not a slab of concrete. What makes this number accurate and reliable? You’re never going to know how accurate your blood sample is until you take a closer look into your individual sample and the machine that analyzed it.

Step 1: Understanding The Science Behind Your Blood Test

First things first! Science is Binary! This means that there are only two possible outcomes. It is either right or it is wrong! The scientific procedure was either done correctly and your sample is accurate, or it was done incorrectly, and the sample is inaccurate. The point is that you will never know and you will essentially be “TRUSTING THE STATE” that your test is accurate. This is something I, as a Wisconsin DUI Defense Attorney who has analyzed hundreds of blood tests, have an extremely difficult time accepting.

Your Wisconsin DUI Blood Sample is analyzed by a process called Gas Chromatography on a machine called a Gas Chromatograph, shockingly enough… This is a process that separates, analyzes, and quantitates compounds in your blood.

Step 2: Testing Your DUI Blood Sample

A little known fact is that even though you took a blood sample, your blood is actually never touched or sampled for blood alcohol concentration.  When you receive a blood draw, the blood is put into a sealed vial and sent to the Wisconsin State Hygiene Lab for analysis.  When the machine ‘runs’ your sample it actually is testing the small amount of air above your blood that was sealed in the vial. A law of physics, Henry’s Law, allows for this because compounds in your blood (a.k.a. alcohol or ethanol) will interact with the air above it.

Step 2: Analyzing the Results

When you receive your individual blood test result back, the piece of paper will have corresponding specification numbers that will allow me to review your individual result, the machine that ran your sample, as well as other samples the machine ran before and after yours. Another important factor to evaluate is the machines calibration. If the Gas Chromatograph that ran your sample is not properly calibrated, how can your sample be accurate?

Step 3:  Attacking Your DUI Blood Test Result

Prior to making any decisions regarding how to proceed forward with a potential case, I always sit down with a client and extensively review the blood test sample. Understanding a blood test, the science behind it, and any potential problems with it is key to determining the best path forward to fighting or resolving a case.  No matter what is found or isn’t found in a blood test, it is always the client decision how to proceed forward.

Hiring An Attorney Who Knows What They Are Doing!

Bottom Line:  Every Wisconsin DUI Offense is essentially Two Charges in One! Fighting the driving, the physical motor skills, Field Sobriety Tests is only half the battle. You have to fight your blood test! You MUST have an attorney that understands the Wisconsin DUI Blood Testing Procedures.

If you have a consultation with an attorney to represent your DUI and they do not know what gas chromatography is… There’s a problem…

Attorney Nathan J. Dineen practices 100% Wisconsin DUI Defense! He is a Certified Standardized Field Sobriety Test Instructor and Drug Recognition Expert. He constantly attends seminars around the nation on Attacking Blood and Breath Testing. If you are going to hire an attorney to aggressively fight your Wisconsin DUI make sure you pick the right one.

Attorney Nathan J. Dineen is available 24/7 and offers a free initial consultation to review your DUI charges. Call 1-877-384-6800.