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How Do You Challenge A Breath Or Blood Test In A DWI Case?

After you are arrested on a DWI charge, there are a couple of things that will happen next. One, before you go to the jail, you are asked whether or not you want to take a breath test, or if you are going to take a blood test. If you say no to the breath test in San Antonio and in surrounding counties, they are going to get a warrant for a blood draw. If you say no to a breath test you are forcing the police to take the following steps

  1. Draw up an affidavit describing why they think you are intoxicated
  2. Convince a Magistrate to sign a search warrant giving them authority to draw your blood
  3. Wait for a Registered Nurse, or another authorized person, to become available to draw your blood.

The above process can take hours. The longer the process takes the less relevant the result of the test is to whether or not you were intoxicated at the time that you were driving. The length of time it takes is one of the inherent advantages of a blood test over a breath test.

Another advantage of the blood test over the breath test is that a sample of your breath is not saved. The State of Texas will not save your breath. There is the machine readout and the machine readout is all that will be left, and so there is no ability for that to be checked.

The machine is supposed to be calibrated once every 30 days. It is checked to make sure that it is working, but it is very important that people understand that the person checking and fixing that machine is an independent contractor whose only client is Bexar County. If your DWI is not in Bexar County the machine is being maintained by an employee of the Department of Public Safety. That person is not an independent in anyway. This person is considered a breath test supervisor, and the Department of Public Safety gives her that authority. The Department of Public Safety is the same agency that is going to receive the funds that you will have to pay if you are convicted of a DWI. The specific fee in question is a surcharge on your license. This presents an inherent conflict of interest.

To recap, when you are asked to take the breath test there are some things of which you need to be aware. You need to be aware that when you take that breath test, there will be no way for an attorney, for you, or for anybody else to double-check

  1. Whether or not that machine was working correctly
  2. There will be no sample of your breath saved
  3. Whether or not your breath was actually at 0.08 or above, or if it was some other different number that might be also true. Because of this, the breath test and the breath test machine are inherently problematic.

If you refuse to take the breath test, then it is likely that you will be required to provide a blood sample. The blood sample is taken by a nurse or another person who is a qualified phlebotomist. The phlebotomist will take that, and they will watch to make sure that the appropriate disinfectant is being used, that it’s not an alcohol based swab, that they do all of those things. There is a checklist that will have to be filled out and it is attached to the search warrant so that your lawyer can confirm that the appropriate steps were followed.

The other thing is that when you balance the inherent unfairness of the breath test, you have inherent advantages in the blood test. These include the following:

  1. The police officer has to go to the magistrate and he has to explain why he thinks there is probable cause that you committed a DWI. This forces the police officer to summarize his case, even it is (as it is in Bexar County) checking a series of boxes.
  2. You have to wait your turn to get your blood drawn. All of this, what your body is doing as you are waiting for that, your body is metabolizing the alcohol. Additionally, the blood result is becoming less relevant to determining you blood alcohol content at the time you were driving. So you have a little of an advantage by waiting to take the blood test. Not only does that blood have to be checked, because they’ll take two samples, they will give you some time essentially to metabolize that alcohol. That will also help lower your result, and then the blood is sent off to a lab.

Still, the inherent disadvantage of getting your blood alcohol level quantified remains. Your blood sample is sent off to a lab that is controlled by the State of Texas. It is not independent in any way, and the employees that will be checking that blood sample are all employed by the same agency that would be taking the funds from you, the surcharge from you, if you were convicted of a DWI. It’s still problematic, but you have the advantage of getting that second blood sample. If you drink one beer and you get pulled over for a DWI, and your blood alcohol concentration comes back much higher than you would expect, your attorney can then get that second sample tested.

For more information on Challenging A Blood Or Breath Test, a free initial consultation is your best next step. Get the information and legal answers you’re seeking by calling (210) 361-3113 today.