DUI evidence: Why Police Did Blood Test v. Breath Test

DUI Arrest Based on Blood Test Results Mesa AZ

The police have discretion of whether or not to conduct a blood test or a breath test following a DUI stop in Arizona. Here are 5 reasons why an officer may decide to conduct a blood test over a breath test:

• Breath Test Refusal by the suspect:
• Suspect is not a good candidate;
• Breathalyzer machine non calibrated or in need of repair;
• Police Suspect a motorist is under the influence of chemical or drugs;
• Initial Portable Breathalyzer Test (PBT) was negative for alcohol.

Breath Test Refusal

In Arizona, a motorist has the option of refusing a breathalyzer test. However if they refuse and police believe they have probable cause to believe a person is under the influence of drug or alcohol, they will get a warrant to conduct a blood test. Also, if a suspect refuses the breath test, their driving privileges will be suspended for one year.

Not a Good Breathalyzer Test Candidate
In order for the breathalyzer test to be accurate or valid, optimal conditions must exist. Police must be sure to avoid substance interference. Medical Conditions such as heartburn or gastric reflux disease may skew the results of a BAC reading. Trial results have proven that stomach fluids may find their way into a suspect’s breath such as chewing tobacco; cough drops; belching or vomiting, or even alcohol may cause interference, causing test results to be inaccurate.


Breathalyzer in Need of Calibration or Repair

The official DUI Breathalyzer Intoxilyzer 8000 must be regularly maintained, and records to support its maintenance needs to be kept. Some machines, especially those that have been in use for a while, may have a history or needed repairs, or be in current need of repairs.


Police Suspect Drug DUI

Circumstances may cause the police to suspect a driver is under the influence of drugs instead of alcohol. Some reasons may include a person admits to being under the influence of drugs; the police witnessed a person using drugs; the police saw an illegal drug in plain sight when they approached a vehicle.

Initial Portable Breathalyzer Test (PBT) was negative for alcohol.
Generally, the police will first conduct a Portable Breath Test (PBT). Arizona does not allow the results of the PBT to be used as the sole source of evidence to obtain a conviction. This is because they are not maintained, calibrated, or subject to strict maintenance reporting guidelines like the official Breathalyzer Intoxilyzer 8000 machine. Its main purpose to either show positive or negative for alcohol use. If the results of the PBT are positive the police will proceed with formal breath test. If the results are negative, but police have probable cause to believe a person is under the influence of drugs, they will proceed with a blood or chemical test.

If you wish to defend your DUI charges, blood test, or breath test evidence you should always retain an experienced DUI attorney to represent you.

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Law Office of James Novak
4500 S. Lakeshore Drive
Tempe AZ 85282
(480) 413-1499
www.Arizonacriminaldefenselawyer.com
www.novakazlaw.com

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