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Chemical Test Defense

Philadelphia Chemical Test Defense Lawyer

Seasoned DUI Attorney On Your Side

When arrested for DUI, you are required to take a chemical test to determine what your blood alcohol level (BAC) is. While the results for such tests are often used as primary evidence in securing a conviction of DUI, they can often present an inaccurate picture of your intoxication levels at the time of driving.

With Parkinson, Tarpey Law, you can fight the foundation of your charges by challenging the evidence presented in a DUI case. Our Philadelphia DUI attorneys have more than 40 years of combined experience, including time as former district attorneys, and can help you build a formidable case against the toughest prosecution.

Challenging Chemical Test Evidence

Because breath, blood, and chemical tests are merely chemical indicators of the presence of alcohol, they are often far from sufficient for upholding your allegations. In addition to the fact that the actual BAC for intoxication varies from person to person, each test may be inaccurate depending on the circumstances in which it was administered. That is why you need a Philadelphia criminal defense lawyer to assist with contesting these results.

Our firm can help you fight your charges by challenging these chemical tests:

  • Breath test: If you have any alcohol in your mouth at the time of a test, the results may be higher than accurate. Additional problems with a breath test may stem from malfunctioning or poorly calibrated testing equipment.
  • Blood test: Because alcohol takes time to absorb into your blood stream, you may be arrested while driving under the legal limit but test with a substantially higher BAC. Additionally, delays in sampling or contaminated tests may skew results unfavorably.
  • Urine test: As with other tests, data can be influenced by inadequate testing methods or equipment. Data for this test may not reflect actual BAC while driving, and certain foods and medication may lead to inflated results.

It is imperative that you retain a legal team with the acuity needed to combat your BAC test results. At Parkinson, Tarpey Law, we have successfully handled numerous cases on the state and federal levels. With experience in defense as well as prosecution, we approach every case with a balanced understanding of the charges are clients are facing, and help them stand against the toughest prosecution.

Contact our firm today to schedule a free consultation with a DUI lawyer in Philadelphia!


  • Reduced Sentence Commonwealth v. A.B.
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  • Found Not Guilty Commonwealth v. A.H.
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  • Not Guilty Commonwealth v. A.R.

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