DWI/DUI Detection In New Hampshire

DWI / DUI Detection in New Hampshire

DWI/DUI detection procedures are set forth by the National Highway Traffic Safety Administration (NHTSA) and documented in the NHTSA “DWI Detection and Standardized Field Sobriety Testing (SFST)” Participant Manual. When talking about a DWI/DUI in New Hampshire, the acronym DWI means “driving while impaired” and is synonymous with DUI, “driving under the influence.”

The entirety of the DWI detection process involves identifying and gathering of evidence in determination of whether or not a suspected individual should be arrested for a DWI violation. The DWI detection process has three phases:

  • Phase One – Vehicle in Motion;
  • Phase Two – Personal Contact; and
  • Phase Three – Pre ‐arrest Screening

The Process Continued

Phase One – Vehicle in Motion

Unless there is a sobriety checkpoint or there has been a traffic accident, DWI detection begins with phase one—observing the vehicle in motion. Specifically, New Hampshire police officers and State Troopers are trained to look for potential drunk drivers by searching for observational cues that may alert them that the vehicle in motion is being controlled by an impaired driver.

The New Hampshire Police Standards and Training Academy teaches the state law enforcement officers to be on the lookout for twenty-four (24) different cues of impairment. These cues of impairment were developed as a result of a study conducted by the National Highway Traffic Safety Administration (NHTSA) and are specifically used by police officers to detect nighttime drunk-driving. The twenty-four cues themselves can be divided further into four categories. They are as follows:

Problems in Maintaining Proper Lane Position

  • Weaving
  • Weaving across lane lines (lane departure)
  • Drifting
  • Straddling a lane line
  • Swerving
  • Almost striking object or vehicle
  • Turning with a wide radius
  • Slow Speed (10 miles per hour + below limit)

Speed and Braking Problems

  • Stopping problems (too far, too short, or too jerky)
  • Unnecessary acceleration or deceleration
  • Varying speed
  • 10 mph or more under the speed limit

Vigilance Problems

  • Driving without headlights at
  • Failure to signal or signal inconsistent with action
  • Driving in opposing lanes or wrong way on one way
  • Slow response to traffic signals
  • Slow or failure to respond to officer’s signals
  • Stopping in the lane for no apparent reason

Judgment Problems

  • Following too closely (tailgating)
  • Improper or unsafe lane change
  • Illegal or improper turn
  • Driving on other than designated roadway
  • Stopping inappropriately in response to an officer
  • Inappropriate or unusual behavior (throwing objects, arguing, etc.)
  • Appearing to be impaired

The “vehicle in motion” phase is completely dependent on a law enforcement officer’s observation of how a vehicle is being operated and, as is evident by the last two “cues of impairment”, the observations can at times be completely subjective to the officer viewing the vehicle in motion.

Phase Two – Personal Contact

In the first phase, the NHTSA manual states that law enforcement officers that are better able to recognize “cues” of impairment when observing vehicles in motion are more familiar with the “clues” of human indicators of impairment shown by allegedly impaired drivers when pulled over during the “personal contact” phase. In all phases of DWI Detection, officers are collecting these "cues" and "clues" of impairment as evidence as to whether or not to make an arrest.

The first task for officers in phase two of DWI Detection is to approach, observe, and interview the driver. At this time, it is quite possible that the officer will ask you incriminating questions and make judgments based on your statements, the personal appearance of the driver or the contents of the vehicle, and even any odors observed when deciding whether or not to move on to phase three—Pre-arrest screening. Additionally, if an officer asks the driver to exit the vehicle, the officer is continuing to collect additional evidence on the level of impairment judged by the manner in which the driver exits the vehicle.

Phase Three – Pre-Arrest Screening

During phase one, the officer has observed cues of impairment which lead to their decision to pull the driver over. Phase two, the officer observes clues which are human indicators of impairment and the officer has asked the driver to exit the vehicle. Now, the officer is on phase three—pre-arrest screening, of the DWI Detection process. During phase three, officers will administer scientifically validated “Standardized Field Sobriety Tests” (SFSTs).

The next steps, according to the NHTSA, depend on specific state laws. In New Hampshire, the first field sobriety test may be one to test dexterity where the driver has to follow a set of instructions by the law enforcement officer that test the driver’s ability to perform specific physical actions, such as “touch your nose” or “walk a straight line.” Police officers in New Hampshire also may also conduct an “Intoxilyzer Test” or "preliminary breath test." This is the point where the driver blows into a small tube attached to a machine that is intended to calculate the level of alcohol on the driver’s breath. At this point, with the evidence collected from phase one and phase two, the officer will also consider the evidence gathered in phase three and decide whether or not the driver will be arrested for a DWI.

Our DWI Defense Attorneys Can Help

The DWI Detection Process, as it is laid out by the NHTSA, is the primary and adopted tool of the New Hampshire Police Standards and Training Academy. Therefore, this is the process that all law enforcement officers in the state of the New Hampshire will use in the detection of a DWI/DUI. It is important to understand the process which is used in DWI Detection; but, it is even more important to retain an experienced New Hampshire DWI attorney who knows the inner workings of this process.

Protecting Your Rights

An individual arrested for driving while impaired (DWI) may face complicated procedures and can potentially face severe punishments. Drivers may not understand that New Hampshire is an “implied consent” state which means that when you drive on a public way, you are by default giving the State of New Hampshire consent to drug or alcohol testing, so long as the officer has reasonable grounds to believe that you are under the influence while utilizing the public way. That being said, you may refuse to perform requested tests, but the refusal results in an automatic suspension of your driver’s license.

An experienced DWI lawyer knows that there are several factors and extenuating circumstances that may present a false-positive during the administration of a breath test. That is why, at Tenn And Tenn, P.A., all of our New Hampshire DWI attorneys are fluent in the laws and science surrounding intoxilyzer tests. In fact, all of our DWI lawyers are certified by the authority of the United States Department of Transportation as Evidentiary Breath Alcohol Technicians qualified to operate the Intoxylizer 5000EN.

If you have been arrested for a DWI or DUI in the state of New Hampshire it is imperative that you quickly retain the services of a skilled and experienced lawyer. A DWI conviction can result in significant penalties, both directly and indirectly. The experienced defense lawyers at Tenn And Tenn, P.A. can help defend your rights under the law, in an attempt to secure a favorable outcome or better—the dismissal of your case. 

Contact the DWI/DUI defense attorney at Tenn And Tenn, P.A. today!


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