Denver area police are trained to look for driving mistakes that indicate that the driver is under the influence of drugs or alcohol. If you are charged, the officer's testimony about your driving mistakes will then become part of the prosecutor's DUI case. For example, swerving, braking erratically, or taking a wide turn may be considered evidence that your ability to drive was impaired by alcohol or other drugs.
The driving mistakes observed by the officer are important in a DUI case for two important reasons. First, it often forms the legal reason why a Denver police officer stopped you in the first place. If there was no valid reason to stop your vehicle, then all of the evidence that the officer collected should be suppressed by the judge – and the case against you may be thrown out. Second, the driving mistakes are used by the prosecutor as evidence that you were impaired.
Driving symptoms of impairment are important evidence for the prosecutor. The police officer's account that you did something wrong, or dangerous, on the roadway creates a bias for the jury that you endangered other people on the date of your alleged DUI offense. This feeling of danger makes them more likely to convict you. Driving mistakes also contribute to the evidence that you were impaired in much the same way as a poor performance on the field sobriety tests do.
If unchallenged, this testimony can be damaging to your DUI case. The jury could be convinced that you were under the influence just from the officer's account of your driving. Your Denver DUI attorney will challenge the testimony about your bad driving at trial. Often, this involves showing the jury that the same mistakes are made by perfectly sober drivers, and should not be considered evidence of impairment. An officer on the stand will usually have to admit that they frequently issue citations in the Denver area for swerving, or other traffic violations, when the driver is not under the influence. There may be other explanations for a swerve or a wide turn, such as being distracted by a cell phone, or having an argument in the car, and so on. Your attorney must work with you to develop a clear understanding of everything that was occurring around the time you were stopped by police.
Effective DUI defense often relies on your attorney's ability to offer reasonable explanations for the driving mistakes, explanations other than that you were impaired by alcohol or drugs. If your lawyer can effectively explain your driving mistakes, it will also help to explain why the officer mistakenly believed that you were intoxicated. In turn, this can help to explain why the officer was biased against you during other phases of your arrest, and why the officer reported a bad performance on the field sobriety tests, or exaggerated his observations of your behavior in his report.
The police usually charge a driver with something in addition to DUI. Most often, the reason you are stopped in the first place is because of another infraction like speeding. The separate charge is often the basis for probable cause for the police to pull you over, and the charge (or charges) will remain attached to your DUI case as it proceeds through court.
Speeding or Weaving
Speeding is not evidence of impairment. People speed every day when that has nothing to do with alcohol or drug impairment. An effective cross examination of the arresting officer must include asking the officer how many times he has cited someone for speeding, and how many of those resulted in DUI arrests. The credibility of the officer can be easily impeached if he tries to argue that speeding is a symptom of impaired driving. Your attorney can then argue that the officer is biased against you, and is trying to offer misleading testimony to convict you.
Weaving, or "Failure to Drive in a Single Lane" as it is called in Colorado, is not by itself evidence of impaired driving. Weaving is one of the most common reasons for the traffic stops that result in DUI arrests. Here again, there are many reasons that a person does not drive in a perfectly straight line. The driver may be momentarily distracted by a cell phone, the pitch of the roadway may be uneven, the vehicle may have mechanical problems, and so on. Cross-examination of the police officer should help to show the jury that no car ever travels perfectly straight, and that all drivers must constantly adjust the direction of the vehicle, even when driving straight. You can see this yourself if you pay attention to how you must continually correct your course, back and forth, while driving down the highway. Therefore, weaving is a matter of degree, and can be based on many factors that do not include drug or alcohol impairment.
If your car has mechanical issues, be sure to mention this to the DUI defense lawyer handling your case, as this information may play an important role in your defense case. If you are planning to take your case to trial, it may even be wise to have your vehicle inspected by a mechanic.
Speeding should never be considered evidence of impairment. In fact, it may actually demonstrate good attention and coordination, if there are no other driving mistakes.