Walckner Law Office

​Attorney James Walckner​​

The prosecutor’s job is to prove its case beyond a reasonable doubt.  This concept is important to understand; it is not an accused person’s obligation to prove she’s innocent.  The defense attorney’s job is to prevent the prosecution from proving its case.  This is done by discrediting witnesses and identifying improper police conduct that may lead to suppression of valuable evidence.  Taking evidence away from the prosecution is how these cases are won.

OUI statute (the prosecution must prove each element beyond a reasonable doubt)

1.      Operation of a
2.      Motor Vehicle on a
3.      Public Way while
4.      Under the Influence of alcohol/drugs, or
5.      Having a Blood Alcohol Concentration (B.A.C) of .08 or above


Unlike many other states, an OUI conviction in Massachusetts does NOT require proof the defendant actually drove a vehicle.

The legal definition of “operation” is the intentional manipulation of the ignition or any mechanical part of the vehicle, or use of any electrical agency, which alone or in sequence will set in motion the motive power of the vehicle.  This means the vehicle does not need to be in motion or running to sustain a conviction.  Operation can be, and often is, proven with circumstantial evidence.

Motor Vehicle

The legal definition of a motor vehicle comes from our statutes and the court’s interpretation of the law.  To be legally recognized as a motor vehicle the conveyance must be “constructed and designed for propulsion by power other than muscular power, including such vehicles when pulled or towed by another vehicle.”  It includes all-terrain vehicles (ATV’s).  Contrary to a common misconception, while cyclists are required to follow “rules of the road,” bicycles, wheelchairs, and mopeds do NOT meet the definition of a motor vehicle in the OUI context.

Public Way

For the purpose of an operating under the influence charge, a public way not only includes roads and highways laid out under authority of statute, but also includes places other than roadways depending on the circumstances.  For instance, a municipal parking lot allows members of the public a right of access, giving it the same legal effect as a public road in the context of a drunk driving charge.  Depending on the circumstances, privately-owned places, such as shopping mall and gas station parking lots may have the same effect as a public way as well.

Under the Influence

In the absence of a breath test or blood test, the prosecution relies entirely on circumstantial to prove a defendant was “under the influence.”  Most of this evidence is subjective, and oftentimes the prosecution and police introduce multiple factors to “stack the evidence” in trying to characterize the driver as inebriated and persuade a jury to reach a guilty finding.  These factors may include the manner in which a vehicle was driven (swerving, crossing over the centerline, wide radius turns, and driving too slow) or what are termed “visible signs of impairment” (odor of alcoholic beverage on the person’s breath, bloodshot eyes, and slurred speech).

Other evidence consists of observations made during standardized field sobriety tests [hyperlink] are supported by statistical relevancies.  Police officers administering such tests are required to complete specialized training and adhere to a strict protocol to ensure the tests are given the same way to every person suspected of OUI.

Blood Alcohol Concentration of .08 or Greater

Under Melanie’s Law, the OUI statute underwent several changes.  The most notable change was creating a per se inference that holds someone with a blood alcohol concentration of .08 or greater is deemed to be under the influence.

Massachusetts OUI Law