Field sobriety tests invalid in determining whether driver is intoxicated by marijuana

With the legalization of marijuana in Massachusetts and Maine and the decriminalization of possession of small amounts of marijuana in Vermont and New Hampshire a new legal front has been established in determining how to measure an individual’s level of impairment when operating a motor vehicle.  The lack of specific scientific evidence as to how to detect impairment is one of the major reasons Vermont governor Phil Scott vetoed a bill to legalize possession of marijuana last year and continues to be a huge concern for Vermont law enforcement in their ability to arrest individuals for driving under the influence of marijuana or other drugs.

The Massachusetts Supreme Court decision in COMMONWEALTH V. GERHARD has now limited police officer’s ability to use the standardized field sobriety tests as evidence of drug impairment, tests which have long been validated to detect alcohol impairment.

“The research on the efficacy of FSTs to measure marijuana impairment has produced highly disparate results. Some studies have shown no correlation between inadequate performance on FSTs and the consumption of marijuana; other studies have shown some correlation with certain FSTs, but not with others; and yet other studies have shown a correlation with all of the most frequently used FSTs.”

As has been litigated in Vermont Courts (and recently won by Attorney Evan Chadwick in a drugged driving case), a law enforcement officer who is not a certified Drug Recognition Expert should not be able to  testify as to their opinion of impairment when investigating an individual for DUI-Drugs .  The Gearhardt decision adds an extra layer of protection for these types of investigations by limiting what evidence can be presented on the roadside investigation.

Vermont DUI attorney passes field sobriety practitioner course

Attorney Evan Chadwick recently completed a four day course that resulted in his certification as a field sobriety practitioner.  Using the same curriculum that trains all police officers, Attorney Chadwick passed both the practical and written test to earn his certification.

“The training I received is vital to my practice of Vermont DUI defense” stated Chadwick.  “By receiving the exact training law enforcement officers receive I am now able to better understand the nuances of the application of the field sobriety tests that may cause their application on the roadside to be questioned.”

Attorney Chadwick anticipates furthering his education in the near future, as he has been invited to attend the field sobriety instructor training this winter, which will allow him to apply for field instructor certification.  “Educating myself on the many facets of Vermont DUI defense has always been my long term goal” stated Chadwick.  “The more I understand the DUI investigation and where mistakes can be made, the better I can serve my clients in ensuring they receive the best defense possible”.


HGN-A Vermont DUI defendant’s worst and possibly best friend.

Horizontal Gaze Nystagmus or HGN is a key tool in law enforcement’s arsenal to investigate an alleged DUI.

Defined as the “involuntary jerking of the eyes that occurs when eyes gaze to the side” the HGN has been validated as one of the most reliable indicators of driver impairment when compared with all the other field sobriety and investigative tests officers employ while on the roadside.

If HGN is conducted correctly a 2013 San Diego validation study has found that it can be 88% accurate in detecting that a motorists BAC is above .08. The findings in an HGN test alone can give an officer the probable cause they need to arrest a motorist and bring them back to the barracks where an evidentiary breath test is taken.

As is the case with all field sobriety tests however, the key determination in the HGN is if the test was in fact administered properly according to National Highway Safety Administration (NHTSA) standards.

As a certified HGN practitioner who has gone through the certification process of administering the HGN, I can say with conviction that the NHTSA requirements are difficult to administer correctly in a controlled classroom environment, let alone in the wide variety of environmental conditions that an officer would face when conducting an HGN test on the roadside.

Timing, position of the stimulus (object motorist is to follow with eyes), medical conditions (such as head injuries) and the surrounding environment are but a few of the many factors that can play a role in the accuracy of the HGN. If any of these are comprised by failing to follow NHTSA guidelines, the entire test and, in turn a significant portion of the DUI investigation can be compromised, leaving serious doubt as to whether the officer has the evidence necessary to charge a motorist with DUI.


Beware! Increased police patrols on I-89/I-91 throughout Vermont this weekend

It is no secret that a holiday weekend brings an increase in traffic driving through the Green Mountain State.  This increase is especially felt on the two major highways which cross the State; I-89 and I-91.  As a result, Vermont Law Enforcement has made it clear that they will be increasing their presence on the highways in order to detect and deter unsafe driving behavior, with an emphasis on investigating DUIs and speeding violations.

According to the Valley News, there has been an expected dramatic surge in the number of vehicles on the road, including on I-89, which sees traffic counts of about 41,000 near the Vermont/New Hampshire state line on an average day.  This surge of traffic resulted in 100 motorists being issued tickets for speed violations and 8 for the use of hand held electronic devices during a joint task force of Vermont and New Hampshire Law Enforcement officers along the Connecticut river valley on Friday.

The interstate’s are customarily Vermont State Police turf.  Do not be surprised to see numerous green cruisers in the median along the highways this weekend.  Although safe driving is always the best defense to avoiding traffic tickets, in the event you find yourself with blue lights behind you, it is important to remember the following:

  1. Be polite;
  2. Be efficient in producing your license and insurance to the officer;
  3. Do not interrogate the officer; and
  4. Keep that PBA care in your pocket at all times and make no mention of it.

Safe travels.