At some point during a DWI (driving while intoxicated) investigation, the officer will usually ask the driver to take a breath, urine, or blood test. The test results show the amount of intoxicating substances (alcohol or drugs) in the driver's system. These results are used by prosecutors to prove DWIs at trials and by the Division of Motor Vehicles (DMV) to determine licensing penalties.
This article gives an overview of New Hampshire's "implied consent" law—which requires drivers to submit to testing in certain circumstances—and the consequences of an unlawful refusal.
Pursuant to New Hampshire's implied consent statute, any person who drives a motor vehicle in the state is deemed to have given consent to chemical testing. Chemical testing can include infrared light breathalyzers, urine tests, and blood tests.
The testing requirement applies only if the driver is lawfully arrested for a DWI. In other words, the officer must have probable cause to believe that the driver was driving or in actual physical control of a vehicle while under the influence of alcohol and/or drugs.
License suspension. Refusal of a lawfully requested chemical test will result in a 180-day driver's license suspension. A second or subsequent refusal carries a two-year suspension. This suspension will run concurrent (back-to-back) with any other DWI-related suspension. (A DWI conviction will result in a separate suspension.)
Probationary license. Drivers with a probationary license who refuse a chemical test will receive a suspension of 90 to 180 days.
Evidentiary uses. When a driver refuses testing, it certainly limits the incriminating evidence the prosecution will have to prove a DWI at trial. However, the fact that a driver refused to submit to testing can actually be used against him or her in the criminal case. A testing refusal doesn't directly prove intoxication, but prosecutors often argue drivers refuse testing in an effort to hide their impairment.
Once a driver refuses testing, the arresting officer is supposed to seize the driver's license, issue a notice of suspension, and issue a temporary 30-day license. The driver can contest the suspension by submitting a written request for a hearing within 30 days of the arrest.