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DUI & DWI Tests – Are They Accurate?

There are many different types of DWI/DUI tests that police officers in the state of Washington may perform. Being charged with DUI in the state of Washington may carry serious consequences and each DUI test may have its pros and cons and each test may have a different level of accuracy.

Field Sobriety Tests

The least accurate DUI test is most likely the field sobriety test. In this test the police officer attempts to assess the balance, coordination, and mental abilities of the individual he suspects of DUI and put their observations on the police report. Some common portions to this test may include standing on one leg, walking in a straight line for a certain distance or a certain number of steps, turn and walk back again, and, finally, the suspected individual may have to watch as the officer moves his flashlight back and forth across the person's face to check for sudden eye movements which may be a sign of being intoxicated.

If after administering this test the officer still believes the person to be intoxicated, they may administer a Breathalyzer test or simply arrest the individual. Of all the tests, the results of a field sobriety test may be considered the least accurate by far because, ultimately, the determination of whether one is intoxicated or not is left up to the discretion of the officer and what he observes. That’s why more accurate tests are usually given in addition to field sobriety tests.

Blood Tests

A blood test may be the most accurate available method of testing an individual’s blood alcohol concentration. However, just because the test may be the most accurate available, that does not mean it’s infallible. Sometimes a good defense to a blood test can be constructed by pointing out flaws in things like the testing procedures and human error.

A good Washington DUI lawyer may be able to discover problems with the test during cross-examination using the chemistry involved. For example, maybe the blood sample was left out too long thereby making the test invalid, or perhaps the testing center did not follow good record keeping practices and there is a possibility that they mixed up the tests. All these questions and more may be raised by an experienced Washington DUI attorney during cross-examination.

Breath Tests

These tests may be done using a Breathalyzer and they measure blood alcohol concentration (BAC) using an indirect method because they are based on how much alcohol is in the air you exhale; not how much alcohol is in your blood. For this reason, breath tests may be significantly less accurate than blood tests.

In addition, an experienced Washington DUI attorney may know about what other doubts to raise. For example, there may always be the possibility of manufacturer defects in the Breathalyzer. Also, some toothache medications, breath fresheners, and mouthwashes may sometimes lead to falsely heightened readings on a breath test.

Urine Tests

The urine test may be typically considered the least accurate test after the field sobriety test. This is because the amount of alcohol in your urine may not be directly correlated with the amount of alcohol in your blood. For example, some individuals may only have 45% as much blood in their urine as in their blood whereas others may have twice as much in their urine as in their blood. The test may also vary depending on how well hydrated you are.

The fact is that every test may have a different level of accuracy. However, regardless of how accurate a test may typically be, an experienced DUI attorney may be able to find an applicable defense. That’s why it may be important to have a capable Washington DUI attorney at your side. At Murphy’s Law Offices, we have years of experience defending individuals from Washington DUI charges and we are ready to help you. A Washington DUI charge may have very serious, potentially life-changing consequences, so act now. Contact Dan Murphy’s Law Offices today for a free consultation.

Call today — (253) 312-6122 — your future may depend on it.

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Murphy’s Law Offices
506 S. 11th St.
Tacoma, WA 98402
Phone: (253) 312-6122

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