In Massachusetts, there are several types evidence typically sought after by police when investigating operating under the Influence (OUI) of Alcohol and/or Drugs charges. These include:
- observations of the manner by which a vehicle was driving,
- observations of the driver,
- statements by the operator,
- the driver’s performance on roadside agility or standard field sobriety tests,
- the driver’s participation in chemical breath tests.
Even though collected by police during an OUI investigation, some of these items of evidence may be inadmissible at trial against a defendant who is charged with operating under the influence.
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Participation in a chemical breath test is voluntary. Police may offer a preliminary breath test to a motorist on the roadside. If a motorist is arrested for OUI, police will offer him an official preliminary breath test at the police station. If a test is offered, it does not automatically mean the breath test result is admissible at trial. In order to offer breath test evidence in an OUI trial, the prosecution must lay an appropriate foundation by following a number of hyper technical steps to establish the reliability of the testing process, equipment and result. If these steps cannot be established, the breath test may be excluded upon a motion by the defense or an objection to admissibility, once offered by the prosecution. Chemical breath test evidence can be very powerful during an OUI prosecution, so the defense should take every possible measure, under the law, to have this evidence excluded at trial.
Because participation in a breath test is voluntary, a defendant may refuse to participate in a preliminary breath test and/or an official breath test once transported to the police station. If a defendant refuses to participate in either test, a skilled defense attorney may file a motion asking the court to prevent the prosecution from offering evidence of the defendant’s refusal during his or her OUI trial. A jury may draw a negative inference that a defendant refused that chemical breath test because he or she was under the influence of alcohol, and believes the breath test would have yielded unfavorable results. Because of this potential danger at trial, the defense should always move to exclude any reference to the refusal at an OUI trial.
Field Sobriety Tests
The law enforcement community, during OUI detection and enforcement, most always administers to suspected motorists standardized field sobriety tests. One of these tests is known as the horizontal gaze nystagmus (HGN) field sobriety test. In layman’s terms, the HGN test is conducted by a police officer asking a motorist to follow, with his or her eyes, either a finger or an object (i.e. pen) moved by the officer left and right or up and down in order to detect the onset of nystagmus. Nystagmus is a condition in which the eyes make repetitive, uncontrolled movements, which often result in reduced vision and/or depth perception and can affect both balance and coordination. The onset of nystagmus is correlated to intoxication, and one of many indicators law enforcement relies on to make OUI arrests, and subsequently, prosecutors rely upon during OUI trials. Because the HGN test has a scientific basis that is not within the common knowledge of a lay person (i.e. police officer), the defense can move to exclude this evidence at trial absent the Commonwealth producing an expert witness to offer HGN test evidence.
Prior OUI Convictions
Sometimes defendants charged with OUI have a prior OUI conviction in their records. Under these circumstances, the District Attorney will charge OUI Subsequent Offense, which is a more serious crime than a first offense. The more prior OUI convictions that are in a defendant’s past the more serious the subsequent offense becomes in terms of punishment, upon conviction. If a defendant is charged with a subsequent offense OUI, the law affords him the right to be tried separately on the issues of both the new OUI charge, and if convicted, if the most current conviction is in fact a subsequent offense. Where a defendant is charged with a subsequent offense OUI, the defense should file two motions. First, move to bifurcate the issues of the present OUI and subsequent offense. Second, the defendant should move to bar the prosecution from offering any evidence that the defendant was previously arrested, charged or convicted of OUI. Knowledge that a defendant had a prior offense of this nature may taint a jury’s ability to be fair and impartial, and may lead them to draw the negative inference that if he committed this crime in the past, he likely committed it again in the present.
Minimizing the admissible evidence in an OUI case is key to obtaining an acquittal after trial, or alternatively, negotiating the most favorable plea deal .