In the recent matter of Commonwealth v. Hourican, the Appeals Court reversed a trial judge’s denial of a motion to suppress breathalyzer test, ruling that the test results were invalid under state regulations. The Appeals Court’s decision is a significant victory for Massachusetts OUI defense attorneys as the Court placed a greater burden on the Commonwealth requiring prosecutors to offer more reliable evidence to establish a defendant’s BAC level to reach a conviction.

The defendant in Hourican was operating a pickup truck late at night when he collided with a Boston police patrol wagon. A Boston police officer observed signs of intoxication and arrested the defendant after the defendant failed multiple field sobriety tests. The defendant later consented to two breathalyzer tests, the first read a BAC level of .121 percent, and the second read .143 percent. The breathalyzer device used was the “Alcotest 9510”.

Although both results were above the statutory limit of .08 percent, the results were problematic in that they differed by .022 percent. Massachusetts state regulations provide that a breath test sequence (two consecutive tests with a time lapse of a few minuets in between) is only valid if the results are within +/- .02 percent of one another.

The issue before the trial judge, and subsequently the Appeals Court, was whether the third digit in the differential between the defendant’s BAC two results should be truncated so as to preserve the validity of the results under the regulation, or whether the third digit automatically invalidates the results as it sets the differential outside the +/- .02 range specified in the regulation.

After reviewing the history of the relevant Massachusetts regulation enacted by the Executive Office of Public Safety, the Appeals Court decided to interpret the regulation literally so as to require the sequential BAC results to be within +/- .020 of each other. Any differential figure outside of this range would invalidate the results and require the Commonwealth to present a valid sequential test.

This holding particularly applies to breathalyzers utilizing a “gas calibration standard” – such as the Alcotest 9510 used in this case – rather than the “liquid calibration standard” used by other devices. The distinction stems from the language of the state regulation itself, which specifically requires that the results of a gas calibrated breathalyzer test be reported to three decimal places, in contrast to liquid calibrated breathalyzer results which are only required to be reported to at least two decimal places. See 501 Code Mass. Regs. § 2.15(1) (2010).

Although the language of the regulation seems clear, the confusion arises from the different sections of the regulations which were drafted at different points in time. More specifically, the regulation was first drafted in 2006 and contained a provision (501 Code Mass. Regs. § 2.56(5) (2006)) requiring that any third or subsequent decimal place be truncated prior to comparing the results. This same 2006 version of the regulation also provided the +/- .02 range within which BAC results in a sequential test must fall, in 501 Code Mass. Regs. § 2.57 (2006).

In 2010, however, a new regulation was enacted requiring that results using the gas calibration standard be reported in three decimal places. 501 Code Mass. Regs. § 2.15(1) (2010). This new regulation, however, did not revise the language used in § 2.57 in the 2006 version which provided the range of validity for sequential results in only two decimal places (.02). Confronted with this inconsistency, the Appeals Court determined that the regulation should be read literally so as to interpret +/- .02 to the third decimal place as +/- .020, thus invalidating the results in this case.

In so ruling, the Appeals Court reaffirmed the Commonwealth’s heavy burden of demonstrating police compliance with state regulations in breathalyzer test administration. The Court reasoned that the critical objectives of Massachusetts DUI law is to require breathalyzer testing to be accurate and reliable. Reading the state regulation broadly, as the Commonwealth suggested, will only damage the reliability of the Commonwealth’s inculpatory evidence, thus increasing the likelihood that an otherwise innocent driver might be convicted unlawfully.

The Appeals Court encouraged law enforcement officers to exercise more caution and diligence in utilizing breathalyzer testing equipment, and invited the Secretary of the Executive Office of Public Safety to revise the regulation so as to be more specific if a different result was intended by the regulation.