Your Boulder DUI attorney may be able to exclude some or all of the evidence against you if the police did not follow the law during your arrest. For example, if you were stopped by the police for an invalid reason, or if you were otherwise denied important rights during your arrest, the evidence against you may have to be suppressed by the court. Depending on how much of the evidence is suppressed, this may lead to an excellent plea offer, or possibly even the dismissal of your case.
Assuming the evidence against you cannot be suppressed, there are several different types of evidence that the district attorney will use to try to prove impairment in a DUI or DWAI case. Often, the police officer's first observation is that the accused is driving poorly, and this allegation will be used later in the case as evidence of impairment. From there, the arresting officer then makes a series of observations, and conducts tests, attempting to gather evidence of guilt. Each step in the process can include human error, machine error, or both. Defense of a DUI charge requires a careful analysis of whether the evidence that was collected is reliable.
Observations of the Defendant's Driving
Frequently in DUI cases, the officer will note some sort of driving mistake as the justification for stopping your vehicle. As mentioned, this will be used both to justify pulling you over, but also as evidence of impairment. Common driving mistakes include swerving, travelling at the wrong speed, taking wide turns, and so on. In accident cases, the accident will of course be used to prove impairment.
Observations Upon Contact
The officer is also likely to include in his report what his observations were at the time he approached your car and spoke with you. In nearly every DUI case, the police report will state that the officer could smell alcohol, and that the driver had slurred speech, bloodshot eyes, slow movements, or any other sign of intoxication. The police will often report that the accused had trouble finding or handling their license, registration, and proof of insurance. The officer will also record notes about the driver's balance when he steps out of the vehicle for further examination.
Statements Made During the Arrest
The officer will ask you questions during your traffic stop, and throughout your arrest. You are not required to answer any questions or to speak at all. Most of the questions will be designed to gather evidence from you. You will likely be asked how much you have had to drink, where you are coming from, and so on. Your answers, along with any spontaneous statements that you make, will be used as evidence against you. In some cases, your DUI attorney may be able to suppress some of your statements from evidence, preventing the prosecutor from using them against you.
The Preliminary Breath Test
The Preliminary Breath Test, also called the PBT, is a test given by the officer using a small device that he carries with him at the scene of the arrest. This test result is not admissible as evidence against you. It is merely a guide for the officer to help him determine if he should investigate you further. You are not legally required to take this test.
Field Sobriety Tests
Field sobriety tests in Colorado include The Walk and Turn, The One Leg Stand, and the Horizontal Gaze Nystagmus Test (HGN). While there are many other field sobriety tests, these are the only three that are accepted by The National Highway Traffic Safety Administration, as they are considered to be the most reliable. If the arresting officer does not follow carefully prescribed steps when conducting these tests, the results should not be considered reliable in court. Your DUI attorney must have an advanced knowledge of these tests in order to effectively challenge the police officer at trial.
Blood Alcohol Level
The police will ask you to submit to a blood or breath test. A test result of 0.05 or higher, but below 0.08 will result in a DWAI charge. However, in this range, there will be no action taken against your driver's license at the DMV because the BAC is below a 0.08. If the BAC is 0.08 or higher, this will result in DUI charges and will also trigger an action to revoke your license at the DMV. Many procedures for testing blood alcohol level must be followed closely to render the results valid and reliable. Experienced DUI attorneys will examine the data for irregularities that will call the test results into question. In Colorado, you are entitled to refuse to take the breath test. However, your refusal to take the test can be used against you in court.