DWI Related Tests

Tests you may be asked to do in a DWI / DUI case

Field Sobriety Tests (Roadside tests)

Blood Alcohol / Drug Test

Breath Alcohol Test


Field Sobriety Tests (Roadside tests)

There are three Field Sobriety Tests (FST) approved by the National Highway Traffic & Safety Administration (NHTSA).

Attorney Hynes has completed the:

Standardized Field Sobriety Testing Certification Student Course (NHTSA Course) -

This is the class that police take in order to be able to administer field sobriety tests.


Attorney Hynes passed this course with a score of 100% and is certified to administer FSTs. You can rest assured Attorney Hynes knows how these tests are "supposed" to be administered, as well as, or better than, the police officer. Besides a breath/blood test, these tests are usually the main evidence against you in a DWI / DUI case. If you or your lawyer don't know how the tests have to be administered to be correct, you can not properly argue the police did them wrong. Attorney Hynes knows police make mistakes and it is his job to point out these mistakes to keep you Not Guilty and not have to lose your license for many months or years.

The first test is the horizontal gaze nystagmus (HGN). This test is the most accurate of the three, but is also the most subjective. In the test, the officer will have you follow a pen with your eyes. He will check for nystagmus, seeing if your eyes jerk/bounce. People who are intoxicated will have their eyes involuntarily jerk when following the object. However, this test, like the others, is only accurate if the police officer does it properly. Many times they will not. Attorney Hynes has experience cross examining officers to determine how the officer failed to give the test properly. Further, medical conditions can affect this test.

The second test is the One Leg Stand. For this test the officer has you stand on one leg for 30 seconds. He then sees if you do other things such as swaying. Medical conditions also affect this test. Especially if you are older, overweight, or have any back, knee, or leg problems.

The third test is the Walk and Turn. In this test you will be asked to take 9 steps in one direction, turn in a certain way, and then take 9 steps back. This is the most complicated test and has many things the officer looks for, which accordingly has many ways the officer will think you failed the test. Again this test needs to be administered correctly and in an appropriate environment. Attorney Hynes knows what to look for to see if the officer did everything by the book, and to question the officer to see if he actually observed what he thought he did.

Blood Alcohol Test

The most accurate of the tests for alcohol is a blood test. This test also can check be used to check for drugs, which the breath test cannot. The test is often given at a hospital. The test must be provided by a certified person. Further, there are steps that person must take to ensure proper administration of the test. You have a right to have the blood sample independently tested, but you have to inform the State crime lab to hold your blood so they do not destroy it.

Breath Alcohol Test

Portable Breath Test (PBT)

There are two types of breath tests police will use in New Hampshire. The first is a roadside portable breath test (PBT). This test measures the alcohol on your breath / mouth alcohol. This test is often grossly inaccurate at it does not detect lung alcohol. This test is always optional, and there is no administrative license penalty for refusing to provide a portable / roadside. It may make sense for you to refuse to give a sample, although the police officer will likely use this decision to decide whether to arrest you.

See my video demonstrating how inaccurate a PBT can be:


Intoxilyzer 5000 EN

The second, more accurate breath alcohol test is the full test at the police station. The present model breath machine being used by New Hampshire is the Intoxilyzer 5000.Before giving you the test, the arresting officer will likely read you a form going over some of your rights in regard to the test. This test is also optional, but if you refuse it, you will lose your license for 6 months or 2 years, in addition to any license loss that may result if you are convicted of the criminal DUI charge.

However, if you give a sample that comes back .16 or higher, you will be charged with Aggravated DWI and face mandatory jail time. It may make sense to ask to speak to a lawyer first, if the police will allow it.

The person who administers the test must be certified, and the machine itself must be certified. A good DWI lawyer will be able to see if the person gave the test correctly, and if the machine operated correctly. You also have the right to get the breath sample you have been provided with independently tested. Attorney Hynes has experience to help.

See Breathalyzer for more information.

How Many Drinks Does it Take to Get to .08?

N.H. DWI GUY owns and can operate an Intoxilyzer 5000 EN. He knows its limitations and its rate of accuracy. Some of you wonder how many drinks it takes to get to a certain BAC. While everyone is different, I made a video to give people an idea of what they might expect. For the test, I drank 4 shots of vodka in quick succession, and I weigh 180 pounds. After waiting the required time-frame, I ultimately peaked at .07.