What Methods Are Used to Prove DUI?
By Dan Noll on September 17th, 2015 in
In order for the police to prove somebody was driving under the influence of alcohol, they need to obtain evidence. This evidence, depending on the case, can be a wide variety of items. For purpose of this conversation, we will focus in on the most common factors or most common ways that police try to prove somebody was driving under the influence of alcohol. The first item or factor that police will look at is the driving. Is the person speeding? Are they swerving? Are they crashed into another vehicle? Is there any indicator based upon the way the person is driving that would lead a police officer to believe that they are under the influence of alcohol?
The second thing the officer will do is, when they approach the vehicle, and have their initial conversation with that individual. Do they smell alcohol? Do the see alcohol? Do they see an empty cup in the car? Is the person’s speech slurred? Do they smell alcohol coming from the individual’s breath? Does the person have trouble finding their driver’s license and insurance card? That’s the second step the officer will look at. Ultimately, if the officer believes or has some suspicion to believe that the person is under the influence of alcohol, they will ask the individual to step out of the vehicle and perform the field sobriety test. The standardized field sobriety tests are given by officers.
Most of the time, they are recorded by the police officers and they are to give a standardized field sobriety test. That would include the whole battery, of which there are 3. The first test is the horizontal gaze nystagmus. That is an examination the officer gives related to the motorist’s eyes. The second test that is given is the walk and turn test. That’s where the officer instructs the individual to take 9 heel-to-toe steps down, make a turn, and do 9 heel-to-toe steps back. The third test is the one legged stand. That is where an individual stands on one foot, raises the other foot, and counts to a number determined by the officer. The officer is theoretically trained on how to evaluate these tests and determine whether or not they observe any clues of alcohol impairment.
The next step the officer would do is request that the motorist take a portable breath test. This is a breath test that is done on the side of the road and will give a reading of whether the individual has alcohol in their system and how much alcohol is in their system. Generally speaking, the officers will use all of that information to determine whether they believe they have probably cause to arrest an individual for driving under the influence of alcohol. However, there is one additional factor that we have not gone over yet. That includes questions the officer will ask the motorist. For example, the officer will ask somebody if they’ve been drinking, how much they’ve had to drink, when was the last time they had a drink, how they’re feeling, do they think they’re under the influence of alcohol.
Those questions are often asked to establish that the person has been drinking and to give evidence from the motorist’s own mouth of how much they’ve had to drink in what time frame. All of those items that we’ve gone over are the most common ways police officers try to obtain evidence of an individual’s intoxication level. After an individual is arrested, they will be taken to the jail or the hospital, depending on the situation. They will be asked whether they will give another breath sample. This breath sample, again, can be used against the individual at trial. They may also take blood, breath, or urine. Any form that the officer requests may be requested. If the individual consents to giving that specimen, that information can also be used against the individual at trial.