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New Hampshire OUI Information

NH Drunk Driving Information

Driving or Operating Under the Influence of Drugs or Liquor Information

The information on these pages gives an overview of operating a vehicle while under the influence (DWI, DUI, OUI) laws and legal issues in New Hampshire. This information was compiled by Attorney Richard E. Clark of Clark and Assoc, LLP in Portsmouth NH.

Disclaimer: The information you obtain at this site is not, nor is it intended to be, legal advice. You should consult an attorney for advice regarding your individual situation. This information is provided here for your convenience and subject to change without notice.

If you have been arrested for DWI or OUI in New Hampshire or Massachusetts, contact Attorney Richard E. Clark immediately for a free consultation.

The stop of the vehicle by the arresting officer

The majority of stops, when a police officer pulls over the suspect driver, occurs from a motor vehicle offense such as speeding or a tail light out, a call from a cell phone informant that observed the alleged driving in an erratic manner, roadblocks, cars pulled over from an accident or that have driven off the road in snowy conditions, to those parked in a lot. Every type of stop, or reason for pulling over a driver, has different legal elements and standards applied to each, determining whether they are valid. Examining the situation thoroughly from the client detention through arrest will permit the lawyer to determine if a pre-trial motion (a “Motion in Limine”) or suppression hearing is warranted. The majority of complaints are usually won on pre-trial motions to suppress, rather than well-worded surprise questioning of the arresting officer as you see so often on TV.

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What should I do if I've been stopped by a police officer and suspected of DWI, DUI or OUI?

First, always be polite to the police officer. Don't say or do anything that can be used against you. Depending on the situation saying and doing nothing may be in your best interest. If you are arrested for DWI, DUI or OUI, retain a lawyer immediately

What should I do if I've been charged with DWI, DUI or OUI?

Always be polite to the arresting officer and prosecutor. Don't say or do anything that can be used against you. You have the right to remain silent, and this is usually your best choice. Do not file a written statement until you have retained a lawyer.

Delay may cause key evidence to be altered. You have a short time limitation to file certain motions or they are forever lost. In many cases, these motions are the key to getting the best possible outcome for your case.

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Requirement for reasonable suspicion or probable cause

The arresting officer can't pull over a suspect without cause or on a whim in violation of the Fourth Amendment or State Constitutional protection. The police can't pull one over to check licenses and registrations where the true intent is to determine whether one is under the influence. When this is done improperly, the inquiry may be subject to a motion to suppress based on constitutional violations. Without pulling a car over, the authorities are permitted to run a check with the Registry of Motor Vehicles. If they find that the owner has a suspended license they have established reasonable suspicion to complete an investigatory stop.

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Exceptions to stops based on reasonable cause that are held valid

Depending on the type of stop, the state is required to have either reasonable suspicion or the higher standard, probable cause. There are limited exceptions where the state does not have to meet either burden. One such exception is the “Community Caretaking Doctrine”. This exception can't be premised where the real intent is to investigate potential criminal activity. The Community Caretaking Doctrine takes place to make sure the occupants of a car are safe, such as checking on a car pulled over on a road shoulder with a flat tire.

Similarly, the “Emergency Exception Doctrine” permits the apprehension of suspects where there appears to be an emergency situation requiring immediate action for the protection of life, property and safety of the public.

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Roadblocks and checkpoints, another exception to the reasonable suspicion based stop

Roadblocks and checkpoints are another method the police use to conduct investigative stops without reasonable suspicion or probable cause. The courts weigh the interference of liberty compared to the benefit to society. Most courts permit checkpoint stops where they found the benefit to society in mitigating injuries caused from drunk drivers. Checkpoint stops must be limited in time. The individual stop must not last more than a few minutes and the roadblock creation is limited in time.

Click for more information about NH's roadblock and checkpoint rules.

Cell phone users commonly call the arresting authorities to investigate questionable drivers. The cell phone caller is either classified as an informant, one that doesn't disclose their identity, or an identified witness. The reliability standards of an identified witness are far lower than that of an informant. The reliability of an informant may be ripe grounds for suppression of evidence. New Hampshire uses a totality of the circumstances standard.

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The Breath Test

The alcohol breath test is a quick method to get the results of the blood alcohol level, or BAC level, while being noninvasive, making it the most common method used in MA and NH. Police certified in administering the breathalyzer conduct the testing. The machine measures the quantity of alcohol in the air of the lungs and calculates the amount of alcohol that would be in the individual's blood based on the figures found. The breath test is a complex mix of science and law. MA uses the Draeger 7110 M. NH uses the Intoxilyzer 5000EN, an infrared device that measures molecular bonds vibrational energy. Although this machine is high tech, it's subject to error. Errors may cause readings to be miscalculated. An innocent party may found in violation when they are innocent.

To mitigate the chance of incorrect calculations, New Hampshire requires two samples to be taken. The tests must be within .02 of each other. If this doesn't happen it will rerun the test and apply the lower of the readings, so long as it is within .02 of the former test.

If there is a problem with the testing on the state's part, we will move to prevent the test from being introduced into evidence during a suppression hearing. It is also important to verify the intoxilyzer machine has been certified to establish the calibrations are correct and it has tested properly.

The breath test is heavily relied on during operating under the influence trials. Whether a bench trial or trial by jury, all those involved give the breathalyzer considerable weight. However, alcohol breath testing is not error proof. Attacking the validity of the breath test results may cause the test to be thrown out in an evidentiary suppression hearing.

New Hampshire's primary alcohol testing device is the Intoxilyzer 5000. You can find more detailed information on this device and its use at the NH Department of Safety website.

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Standardized Field Sobriety Tests

The testing determines the driver's divided attention ability. Divided attention is the individual's ability to comprehend, follow directions while simultaneously testing their abilities such as balance. In theory we need similar attributes to drive safely. Standardized field sobriety tests are subjective. It's up to the test conductor to determine whether the test taker passes or fails by their observations and interaction with the driver. Some of the tests are the Horizontal Gaze Nystagmus Test, One Leg Stand, and The Walk and Turn Test.

There are many methods used to attack the credibility of the tests. The police officer doesn't know the driver. He or she may be unaware of physical or characteristic traits of the one being tested that would lead them to mistakenly believe the driver is under the influence. Some of the traits may include a lisp, physical impediments, English as a second language, glossy eyes from a cold, to wearing high heels while conducting the One Leg Stand Test. Just because a law enforcement officer determines you failed the test doesn't mean a jury would find you were operating while under the influence of alcohol.

The location of the testing may be problematic for the state. The tests are usually conducted on the road shoulder wherever the driver pulls over. The area may be uneven, gravel and snow covered, or rainy. A review of the site may be crucial to sustaining a verdict of not guilty. I would always recommend taking pictures of the area as soon as possible. I've seen instances when a client delayed in retaining me to represent them. When we viewed the site, the rough uneven road shoulder had just been paved. One of my key arguments had just been eliminated. There are many reasons that delay will jeopardize your DWI or OUI representation. Some of them are listed below.

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NH Administrative License Suspension and Hearings Process

If you drive, operate or attempt to operate a vehicle upon a public way, or operate or attempt to operate a boat upon public waters you are subject to testing for the purposes of determining whether you are under the influence of intoxicating liquor or controlled drugs.

After being arrested for an offense arising out of acts alleged to have been committed while you were driving under the influence of alcohol or drugs, the arresting officer will inform you of your rights. If you submit to a blood, urine or breath test which shows an alcohol concentration of 0.08 or more (or if you are under the age of 21, 0.02 or more), your New Hampshire driver's license/operating privileges, non-resident operating privilege, and boating privileges will be suspended. The length of license suspension varies from 180 days to two-years depending on the refusal to submit to the tests, results of the tests and whether it is a first or subsequent offense.

There a many statutory prerequisites to alcohol tests. The testing must also be completed in a specific manner. If the numerous requirements are not properly followed, the administrative hearing will be dismissed and the client's license suspension rescinded. However, this is difficult where the threshold is reduced from guilty beyond a reasonable doubt to preponderance of the evidence. Recent decisions have also given the state substantial deviation from straight interpretation. The rules of evidence are much more relaxed. The hearings may be a method to find facts, force an officer to make recoded testimony while under oath for the future trial, or to defeat the license suspension so it may be reinstated. The client may also waive the Administrative License Hearing.

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Impaired Driver Intervention Program: IDIP

If you are convicted of your first DWI offense, in addition to any fines, you may have to attend either the Impaired Driver Intervention Program (IDIP) or Weekend Impaired Driver Intervention Program (WIDIP). These are 20-hour classes, plus additional time for interviews and assessment. The classes are spread over several days and are at your expense. The assessment could result in a recommendation for additional counseling (“aftercare”) so the program will cost you substantial time and money. In addition, for these classes you must supply a Certified Motor Vehicle Record, at your expense.

More information can be found at the NH Department of Safety website.

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Alcohol Ignition Interlock Devices

An “Alcohol Ignition Interlock Device” is an instrument that is attached to the dashboard of your car to prevent you from starting it if you have been drinking. Before you start your car, you must blow into it and it will calculate the amount of alcohol in your breath. They are usually set to not let you start your car if your level is above 0.02%.

The court may order this device installed in your car as a condition of reinstating your drivers license after being convicted of DUI/DWI/OUI or as part of a negotiated agreement as an alternative to full license suspension. The cost of installation and other associated fees are your responsibility. More information about this device can be found at the NH Department of Safety website.


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