Challenging Your Breath, Blood, or Urine Test Results

A number of issues must be considered in a DUI case:

  • Did the officer have probable cause to pull you over?
  • Was the sobriety field test administered correctly?
  • Are the results of the breathalyzer, blood, or urine test reliable?

I'm OWI / DWI / DUI defense attorney Craig Kuhary with the law firm of Walden & Schuster, S.C. I understand how to identify and expose mistakes on the part of arresting officers when field sobriety tests are improperly conducted or when DUI chemical tests are tainted and unreliable. I also determine whether an arresting officer made any attempt to determine if my client had an inner ear problem, suffered from a chronic illness like multiple sclerosis, or simply couldn't perform the tests as requested.

If you've been arrested on a drunk driving charge, contact me today. I challenge DUI charges and uncover mistakes that happen more frequently than people realize.

Blood Test Kits and DUI Arrests

More and more police departments are using blood tests instead of breathalyzers to determine a suspect's blood alcohol content (BAC). While a blood test may be more accurate, it is not foolproof nor does it test simply for alcohol: blood tests will also determine if you have illegal drugs in your system - even if the last time you used drugs was two or three weeks ago. For this reason, it's important to challenge blood tests under certain conditions.

In the state of Wisconsin, blood can only be drawn by a certified person. Typically, a blood kit is used that is composed of glass vacuum tubes coated with preservative to prevent coagulation of the blood. When the blood is drawn, a specific procedure must be followed to ensure the blood and preservative is mixed correctly. Additionally, if the lab technician swiped a suspect with an alcohol swab, the sample may be tainted as well. Here, it's important to ask the following: was the kit used expired? Was the sample tainted by too much preservative or salt in the tubes? Was the sample drawn primarily whole blood or mostly serum or plasma?

DUI Arrests and Breathalyzers

The Intoxilyzer 5000 - used by many police departments - operates according to Henry's Law, positing a blood to alcohol ratio of 2,100 parts of breath for every 1 part of blood. Recently, more and more forensic specialists have questioned the reliability and accuracy of the Intoxilyzer 5000, demonstrating how several different factors can result in a false positive.

If a different breathalyzer was used in your arrest, whether or not it was properly calibrated, whether the mouthpiece was changed between sample breaths, and how hard an officer asked you to blow into the device can affect the results as well. Additionally, a breathalyzer's results do not necessarily reflect BAC at the time a suspect was driving, but rather when the test was given. Consequently, if a person is borderline .08, making them wait to take a breathalyzer may not reflect their BAC while they were actually driving.

Urine Tests and DUI Arrests

Urine tests also require a set procedure that involves asking a person to urinate and then wait 20 minutes before providing a test sample. By itself, however, urine tests are not as accurate as blood tests since water can remain in a person's body over a long period of time. This is particularly important in cases where a person's BAC is near or slightly over .08.

Additionally, urine tests are sensitive to drugs in a person's system. Traces of heroin, cocaine, and marijuana can be detected in urine tests. However, certain over-the-counter medications can also trigger a false positive for drugs in a person's system. For these reasons, it's important to carefully review the results of a urine test and challenge evidence that may have been compromised by the manner in which the sample was taken and the time period involved.

Challenging DUI Charges - Contact Attorney Craig Kuhary Today

Don't let a DUI arrest create legal and financial complications in your life. Contact me, DUI defense attorney Craig Kuhary, to schedule a free consultation. We can challenge the DUI charges against you.