Many people believe that BAC tests are indisputable and guarantee a conviction in Pennsylvania DUI cases. While they’ve certainly been painted that way, and both the police and prosecutors often view BAC as conclusive proof of impairment, BAC tests are not beyond dispute. They, just like almost any other medical test, do have a margin of error. Before you give up on your DUI case because of a supposedly high BAC result, learn more about these tests and your legal options.

As a member of the National College for DUI Defense and previously ranked among the 10 best by the American Institute of DUI/DWI Attorneys, Chester County attorney Michael Skinner has extensive experience in this area of law and can pinpoint the inaccuracies in both breath and blood chemical test devices.

To discuss how you can overcome a potentially faulty BAC result and avoid the consequences of DUI, call (610) 436-1410 to schedule a free consultation.

Which DUI Tests Are Most Accurate?

Perhaps the most reliable Blood Alcohol Concentration (BAC) test is a blood test. This means that it is often the most difficult to challenge in court. However, there are still factors that can impact the validity of a blood BAC screening, like the validity of the warrant, the chain of evidence with the lab, and possible contamination.

Breathalyzer tests conducted at a medical facility or police station also tend to be highly accurate. Don’t confuse these with roadside breath tests, which are optional and much more flawed. Although the mandatory breathalyzer tests are likely to be accurate, they still need to be maintained and are prone to inaccuracies.

BAC Tests with a Higher Rate of Errors

Some breath screening devices are much more likely to have serious errors that could lead to an unfair conviction. For instance, roadside breathalyzer tests are known for being unreliable. This device is not properly calibrated and maintained to produce accurate results. While a roadside breathalyzer result may provide enough evidence to arrest you, it’s likely that they’ll use other screening methods for evidence against you at trial.

Urine screenings are also notoriously unreliable, which is why they are no longer admissible as evidence in DUI cases in Pennsylvania. The amount of alcohol in your urine may not be a true reflection of your blood alcohol content.

Why BAC Tests Are So Unreliable

BAC tests, like blood tests for example, can be compromised by using an expired test kit, a sample drawn incorrectly, or by improperly handling the blood sample. Additionally, consumption of certain substances or medications could change the test results.

Breathalyzer tests rely on machine accuracy. If the machine is not cleaned, maintained, and calibrated on a precise schedule, it can produce inaccurate readings.

Most BAC test errors happen because of:

  • An inherently flawed screening method
  • Human error
  • Improper sample collection procedures
  • Machine error

Many who are accused of driving under the influence do not know that these test results can be challenged and may even be unusable in court. Working with an attorney with extensive knowledge of local DUI laws and procedures is essential.

What If You Suspect Your BAC Test is Inaccurate

If you believe that your BAC blood, breath, or urine test may be an inaccurate reflection of your impairment level at the time of your arrest, it is important to move quickly. An attorney who knows how to find the flaws in DUI screenings is a significant advantage when you’re facing DUI charges. The longer you try to handle a DUI on your own, the easier it is for the other side to use inaccurate DUI tests to build a strong case against you.

Turn to Skinner Law Firm for Help

After a Chester County DUI arrest, reach out to Skinner Law Firm to discuss your case. We understand the potential consequences of a guilty plea and we fight aggressively on our clients’ behalf to avoid convictions and minimize any negative impact. With a record of helping clients show the faults in improper BAC testing, we may be able to help you secure a dismissal, reduced charges, or another favorable result to your DUI charges.

For more in-depth advice, call (610) 436-1410 or contact us online to set up a free initial consultation.

Article Author

Michael J. Skinner, the founder of Skinner Law Firm LLC, is a former prosecutor with the Chester County District Attorney’s Office.

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