What Happens In the Lab Does Not Stay in the Lab: Science and Your DUI Test Result

DUI Blood Sample

“If I had been blindfolded and led in somewhere and then the blindfold had been taken off revealing the scene, I would have thought I was in a Third World Country,” so said an esteemed scientist and auditor of law enforcement labs – places where your blood and other body fluid samples are tested – about the Santa Barbara County forensic testing facilities. Is it shocking that even an affluent community could suffer from deficiencies in the sample-testing environment that could cause errors in your test result? Sadly, it should not surprise us, once the full scope of problems plaguing labs is revealed. In order to evaluate the validity of your sample test result, it is necessary to turn an investigative eye toward the environment in which it was “created”. There are a number of scientific issues that may arise which lead to errors in your blood test result.

First, it is important to note that, in any DUI case, any value given, from .08% to .28% and beyond, is only an “estimated” value, not a “true” value. It is impossible to know the true value of a sample. Scientists generally must admit a so-called “margin of error” of 10% to be reasonable, although some labs cling to an assertion of 3-4% error only. Labs should have written guidelines and protocols in place for sample collection, preservation, and maintenance to insure the integrity of that sample and to insure that the end value produced is the best possible estimate. If a lab fails to have written guidelines on these points, it does not mean that standards are thrown out the window; the proper guidelines, which are always in place, are known as Best Scientific Practices.

In the blood sample context, there are a number of protocols within the lab that must be adequately observed for any test result to potentially be an accurate reflection of blood alcohol level at time of driving. First, we need to take a look at the collection environment, or where the blood is collected. In some environments, collection may take place in an atmosphere in which the sample is exposed to contamination by so-called “volatile organic compounds” in the air. In fact, samples can be so susceptible to contamination that even a person passing by wearing perfume or aftershave (substances which both have an extremely high ethyl alcohol content) can have an impact that results in a erroneously high blood alcohol content (or BAC) sample reading. Second, we must look at what tools and techniques are in use. In this area of equipment, it is necessary to obtain records to fully investigate the background and accuracy of the tools used in evaluating your specific sample, including records to establish proper maintenance, inspection, and working order of all testing equipment used – as well as the qualifications and conduct of the person doing the blood draw and the person analyzing the sample.

When it comes to the testing tube in use, there is only one type of tube that is authorized for use in testing a DUI blood sample. Despite this fact, some labs veer off course from what is scientifically acceptable and insist that they have found a way around this requirement. Not so. A 10 ml volume tube is specifically required to achieve the proper ratio of blood to additive for testing purposes. As noted by the manufacturer of a 10 ml tube, anything less will result in a compromised result. A second issue could arise through the manner in which the analyst uses the tube. Tubes must be filled to the point at which the vacuum is activated. Anything less will likewise result in an inaccurate result. Further, preparation of the blood draw site is critical. Per Best Scientific Practices, the analyst must swab the site in a circular motion for a period of thirty seconds in order to adequately disinfect. He or she must then allow that disinfectant to dry for the required period of thirty seconds before injecting the needle for the blood draw. A failure in either area will result in a contaminated sample. Injection into a site which is not adequately dried, for example, could lead to the alcohol-based disinfectant actively seeping into the blood draw. Generally, the tubes in use come pre-treated with the additive for combining with a person’s blood for the test. Although these tubes are “certified” by the company as including an amount of additive which is proper for the testing environment, the best scientific practice of an individual analyst would be to individually test and verify the level of additive prior to use.

Once the blood sample is in the vial, the analyst must mix the sample with the additive in a specific, prescribed manner, so as to make sure that the additive is adequately dispersed throughout the sample for testing purposes. When investigation is conducted of what actually goes on in labs, cases in which standards are not met – and test results, are, therefore, compromised – are revealed. In one case, a video was fortunately available when an analyst indicated that “I did it the way I always do it”… in this case, the video revealed by half-heartedly turning the vial only part way upside down (rather than performing the full inversion from top to bottom that is called for) and failing to complete the required number of inversions required for effective mixing. Given that this was her standard means of practice, her woefully inadequate performance could have affected the validity of thousands of test results and the outcome of thousands of cases in her twenty year career.

In the wake of recent reports about falsified test results, the public is learning to be less trusting when it comes to law enforcement analysts’ assertions of the infallibility of their labs and test results. In one recent case in New York, it was found that the wrongful actions of just one analyst who had mislabeled samples, falsely reported positive results without testing, and lied about her own qualifications, had affected upwards of 20,000 cases.* Similarly, a recent investigation of FBI crime labs found that almost every analyst had “over-stated” his or her results in a way that favored the prosecution over a twenty year period prior to 2000. Of 28 examiners with the FBI Laboratory’s microscopic hair comparison unit, 26 overstated forensic matches in ways that favored prosecutors in more than 95 percent of the 268 trials reviewed so far, according to the National Association of Criminal Defense Lawyers (NACDL) and the Innocence Project, which are assisting the government with the country’s largest post-conviction review of questioned forensic evidence.

Even when the individual analyst is not engaged in deliberate deceit or wrongful conduct, mistakes can be made, mistakes which strike at the very heart of the test result itself. While problems have repeatedly manifested in labs throughout the nation and drawn short-lived public outcry once brought to our attention, little has been done to address conditions or to improve outcomes. A National Academy of Sciences’ 2009 study of forensic science, which looked at the operation of crime labs, identified the following major problem areas, among others:

  • There is wide variability in forensic science disciplines, not only in techniques and methodologies but also in reliability, error rates, reporting, research, general acceptability and published material;
  • Many labs are underfunded and understaffed, factors which contribute to case backlogs and likely makes it more difficult for lab workers to do as much as they could to avoid errors;
  • Most labs operate under the auspices of law enforcement agencies, making them susceptible to pressures—overt and otherwise—to produce the kinds of results that police and prosecutors are looking for;
  • Rigorous and mandatory accreditation and certification programs are lacking, as are strong standards and protocols for analyzing and reporting on forensic evidence. Only a few states require crime labs to be accredited, though in 2005 more than three-quarters of all such labs were voluntarily accredited by private accrediting agencies —the vast majority of them by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board,aka ASCLD/LAB.

“In short, the quality of forensic practice in most disciplines varies greatly because of the absence of adequate training and continuing education, rigorous mandatory certification and accreditation programs, adherence to robust performance standards and effective oversight,” the report noted.
The National Academy of Sciences report presented 13 recommendations for improving the system, including creating an independent national institute of forensic science to lead research efforts, provide education, and to establish and enforce accreditation and certification standards for labs and practitioners. The report also recommended removal of all crime labs from the administrative control of law enforcement agencies and prosecutors’ offices, creation of standard terminology for reports and testimony, increases in funding for peer-reviewed research into the scientific validity of various forensic techniques, more research into human observer bias, establishment of routine quality control and quality assurance measures, and development of a national code of ethics for all forensic science disciplines. As of today’s date, nothing has been done to address these deficiencies or to move toward the improvements envisioned for a more fair and just system.

We bring these deficiencies to your attention to let you know one important thing: that the test result is not the end of the line in your case. This article addresses only the problems that can – and do – occur in a laboratory setting that can lead to an inaccurate test result in your case. Beyond the problems within the lab, there are numerous other factors that could result in a test result that is not truly representative of your blood alcohol content at time of driving. In light of the lack of oversight by the forensic science community in the areas of DUI science, your criminal defense attorney is your front-line of defense of your Constitutional rights and personal freedom. We can help the jury to understand that machines are not infallible, people are not infallible, and that the test result, so often presented by the prosecution as an unshakeable piece of evidence in your DUI case, is only as good as what went into creating it. Partnering with experts in the fields of forensic toxicology and esteemed scientists who know what is required to hold labs to the highest standards, your defense attorney works for you to bring your rights to life and to hold the system to its promise: that it is more than just a system; it is a justice system.