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DUI Breath Tests versus Blood Tests

If I get arrested for DUI, is it better to choose the BAC breath test or the BAC blood test?

Different Los Angeles DUI lawyers feel differently about this issue. Some excellent Los Angeles DUI lawyers recommend the breath test. Other top Los Angeles DUI lawyers advocate the blood test. There is merit to each position.

The BAC breath test is much less accurate than the blood test. More things can go wrong. There are more ways a breath test can generate falsely high reading. This is good in that with the breath test, the Los Angeles DUI lawyer has more bases on which to attack the reliability of the results. On the downside, however, the breath test is more likely to give a falsely high reading and thus wrongfully hit an innocent person with a DUI charge.

The DUI blood test is more accurate than the breath test (though certainly not immune from error and problems itself). But the blood test is less likely to generate a falsely high reading. There are less ways for the California DUI lawyer to attack its reliability.

However, one particularly good thing about the blood test is that the officer does not know the BAC result prior to writing his DUI police report (since the blood takes days to be analyzed for BAC, and the police report must be written right after the DUI arrest). Thus, the officer cannot “tailor” the facts to fit the predictable symptoms of the particular BAC level.

Consider an example. We've had blood tests come back with a .25 BAC level. Anyone at this level should be absolutely inebriated, literally falling down drunk. But in the DUI report, the person is portrayed as only slightly buzzed…while still coherent, alert, coordinated and under control.

We know in this case that the .25 BAC just couldn't be right. It doesn't match up with the cop's observations. There is a “disconnect” between the alleged BAC reading and the predictable symptoms of intoxication that we would always expect to see at that level of intoxication. However, if the cop had gotten to see the .25 BAC reading before writing the DUI report, he probably would have exaggerated the symptoms to make the person look much more intoxicated.

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DUI cases are rarely hopeless. DUI convictions are almost never inevitable. Clients retain our California DUI defense attorneys for one reason: they want to fight the case. And win.

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The police arrested you for DUI. You gave a blood or a breath sample. The DUI officer confiscated you drivers license. The police released you with a notice to appear in court in a few weeks. Where do you go from here? Our lawyers are here to guide you step by step.