DUI Bench Trial Burden of Proof

The “burden of proof” in a DUI bench trial is the same as in a jury trial. “Burden of proof” refers to who has the requirement to prove something. As to criminal charges, the burden of proof is on the prosecution to prove that you are guilty of driving under the influence or driving while intoxicated beyond a reasonable doubt. The burden never “shifts” to you to prove your innocence.

Once a defendant has claimed an affirmative defense (like justification or entrapment), in some jurisdictions the burden to prove that this DUI defense lacks a basis is on the prosecution. In other states, the party asserting the affirmative defense must “come forward” with his or her proof. Then, the prosecutor can seek to disprove the defense.

The prosecutor must prove that your breath test and blood test were given properly.

For any chemical test that was used to determine your blood alcohol level (either blood or breath) or that you had drugs in your system (blood or urine), the prosecutor is first required to prove that the tests were performed in a valid and proper manner. However, once the prosecutor has met this burden, it is then up to your criminal attorney to prove (to put forth evidence) that these results should not be accepted as being reliable by the judge. In the alternative, your attorney may have a way to argue that the results are totally inadmissible.
The biggest and most important presumption in any trial is that you are innocent until proven guilty. This is different than on an appeal of a guilty verdict, where the verdict is presumed to be correct. Once a breath or blood test result is admitted, a presumption (inference) arises that the law enforcement officer did his or her duty in administering the test and that these duties were performed correctly, until the contrary is shown. Without doubt, once the State’s breath or blood test result is admitted into evidence, your attorney will need some proof (usually by way of an expert witness) that the test result is not reliable or accurate.
Every state can pass statutes allowing evidentiary “inferences” (presumptions) regarding what any breath or blood test “numbers” mean. In most states, an inference of non-impairment will arise if your test results are at 0.05 grams or below. Most state statutes that deal with these “low” numbers state that “it shall be inferred” (or “it shall be presumed”) that the driver was not impaired.

In considering the “common law” form of DUI-DWI, this inference of non-impairment applies to both drivers age 21 and older, as well as drivers under age 21. However, drivers under age 21 will face an uphill battle on the underage DUI per se case where a limit of 0.00, 0.01 or 0.02 applies.

Similarly, many states have inferences that give the prosecutors an edge when the “number” is 0.08 grams or more. The state law may provide that an inference of impairment would then exist, but that this is subject to being rebutted by the defendant.

These statutory inferences were originally created more than three decades ago to help prosecutors get convictions, because jurors during those years were quick to render “not guilty” verdicts. In truth, a 0.08 BAC level is not supported by medical proof that all individuals are too impaired to drive at such levels. That number was decided upon as a result of many factors, including a changing political climate and an evolving public awareness of the risk of impaired drivers being involved in accidents.

What about a DUI blood test for drugs?

Almost none of the states have statutory presumptions of a driver being under the influence of drugs if your blood or urine tests reveal a certain number (nanograms per milliliter or cubic centimeter) of a particular chemical or drug. Such a law setting forth presumptions on several categories of drugs does exist in Virginia and Nevada, with Ohio and Georgia possibly soon to follow. However, the refusal to take a blood test may be considered evidence creating an inference that the test would have shown the presence of a prohibited substance. Do not confuse these rules relating to “inferences” of impairment by drugs with statutes prohibiting driving with ANY amount of a contraband substance in your system (the so-called per se drug laws).