Defenses that work
Most people who are charged with DWI have one goal in mind. To remain not guilty and keep their license, or to minimize any license loss. For this article I will just be focusing on defenses that work in a criminal case, to keep you not guilty. Some of these defenses, particularly breath/blood defenses, are best shown when the accused is able to afford an expert witness.
1. Invalid Stop
The police need reasonable articulable suspicion to seize you, i.e. stop your vehicle. If they do not, a motion to suppress can be granted which will prevent all evidence after that point from coming in. The effect of this is you will be found not guilty.
2. You were not the driver
One of the things the State/ Police, must prove beyond a reasonable doubt is operation/ attempted operation of a motor vehicle. They must show you were the one driving. Oftentimes, the driver has already left the vehicle by the time the police show up. This is an ideal case to argue you were not the driver.
3. Your BAC (blood alcohol content) was lower at the time of driving/ you were not impaired at time of driving.
The State must show your BAC at the time of driving/ impairment at time of driving. Two related defenses to this are when a driver is not found in his vehicle and can raise doubt showing he drank after driving. The other is that the driver drank alcohol right before driving, and accordingly the alcohol has not been absorbed into the system yet (rising alcohol defense).
4. The breath machine is not accurate
All breath tests make assumptions, and are not as accurate as blood tests. There are numerous defenses related to breath tests. They generally fall into the category of machine limitations, mistakes by the police in administering the test, and limitations of the Defendant.
One machine problem includes a partition ratio (an assumption of 2100:1 converting BrAC (breath alcohol contentration to BAC (Blood alcohol concentration).
Another problem is mouth alcohol. Sometimes, the machine will be detecting mouth alcohol (which is not alcohol which will impair you), instead of alveolar/lung breath. To attempt to fix this, the operator must wait 20 minutes and make sure you did not put anything in your mouth, burp, or regurgitate. Portable breath tests are especially susceptible to this problem as New Hampshire Police officers rarely check or waits 15-20 minutes.
Finally, the machine must be certified and calibrated every 6 months. Even if it was working when last checked, that does not mean it was working properly when you used it.
One Operator problem includes not being certified to administer the test. Another is failing to follow all regulations in administering the test.
Two common problems with the Driver relate to giving an improper sample, or not being able to give a sample.
Some drivers have medical conditions, particularly diminished lung capacity, that prevents them from giving a breath sample. The police will then deem you a refusal and use this against you. A good DWI Lawyer can show the refusal should not count against you, and may even count against the State.
GERD. Some people have gastro-oesophageal reflux disease. This allows them to essentially regurgitate/burp, in a small amount so that they or the officer do not know it happened. This leads to mouth alcohol which gives an inaccurately high breath sample.
5. The Blood test is not accurate.
There are numerous problems related to blood tests. Sometimes the cop will use an expired kit. Sometimes the phlebotomist (person who draws the blood) uses an alcohol swab or does not put the blood into a tube using an anti-coagulant (this in theory inhibits fermentation which makes alcohol actually grow in your blood). Sometimes the officer or State lab will not properly store the blood at low enough temperature which can lead to fermentation. Sometimes the State can not prove a chain of custody showing the blood drawn and analyzed was actually yours.
6. You were not under the influence
Some of the strongest evidence the Police use to show impairment is Field Sobriety Tests. Often, the tests are not administered properly, which goes to either the strength of the evidence, or can even prevent the test from being admitted into evidence.
Even if the tests were given correctly, many types of medical issues, including age, weight, back problem, leg problem, eye problems, etc. affect the validity of the test. NHDWIGUY is certified to administer field sobriety tests, and has more training in Field Sobriety tests than most police and prosecutors.
7. You were not on a "way"
The State must show you drove on a way. This is generally defined as anywhere the public has access to. You should not be convicted if you were driving on distinctly private property, such as your own lawn or some other road the public should not have access to.