If you are arrested, you must do everything you can to protect your rights. Any attempt you make to explain the situation, and anything you do that can later become part of the testimony used to convict you, will only make your case more difficult to defend. The United States Constitution guarantees you the right to be free from self-incrimination. That is why, when the police officer arrests you, they tell you that you have the right to remain silent. Exercise that right!
Once you have been read your Miranda rights, you must inform the officer of your intent to remain silent, but even if you forgot and began talking, you can stop at any time without it being used against you. Do realize that your right to remain silent does not prevent you from having to cooperate with the officer and provide your name, identification, proof of insurance, etc., but you do NOT have to answer questions about where you were, what you were doing, how many drinks you had, or anything else related to your arrest.
Unless you are in an accident, injure someone or are stopped at a sobriety roadblock check point, you will most likely be stopped based on an officer's reasonable suspicion that you are driving while intoxicated or for another motor vehicle violation. Reasonable suspicion is less strict than probable cause, which is required to arrest you. New Hampshire's exact requirements for probable cause have not come through the courts and remain ill-defined, but cases have been overturned for lack of probable cause. In court, the police officer may be required to testify about what gave them probable cause to arrest you, which may include your physical appearance at the time of the traffic stop (having bloodshot eyes, slurring your speech, weaving or being unable to control your gross motor functions), the odor of alcohol, evidence of alcohol containers visible in your vehicle, or your inability to pass sobriety field tests.
Remaining silent is critical to preventing the officer from obtaining any evidence that may later be used in court to incriminate you. While you should be polite and cooperative about providing your identification and registration, the officer will be asking you questions, not to hear the answers, but to identify if you are slurring your speech or have the smell of alcohol on your breath.
Trying to explain what you were doing, where you were going, or how much you had or had not been drinking will NOT help you avoid arrest. Remaining calm and polite, not fumbling around for your information, and speaking clearly when you must speak are important details. Keep your answers short and to the point; do not become belligerent.
This post contains excerpts from The DWI Book, the definitive guide to protecting your rights in the face of New Hampshire's tough DWI/DUI laws.