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Massachusetts OUI Lawyers challenge the accuracy of the Breath Test Machine in upcoming Statewide Hearing in Concord District Court

Massachusetts OUI Defense lawyers will have the opportunity to challenge the accuracy and reliability of the breath test used in the State in a State wide hearing that will be heard in the Concord District Court.

The hearing has yet to be scheduled with a status conference coming up on September 17, 2015. The primary issues are anticipated to be the following:

  1. Discovery issues regarding the out of calibration regarding the breath test that prompted numerous counties to stop using breath test evidence for several months throughout the summer.
  2. Whether errors in the computer source code of the breath test 9510 make the machine unreliable scientifically.

Out of Calibration Issues

The out of calibration issue arose in April of 2015 and came out of reports that the breath test machine was permitting breath test result when the machine should have alerted the operator to an error in the testing. There were two types of situations that came up. One was on the test ticket itself. A breath test ticket looks like this:


Air Blank: 0.00

Subject Test:  .133

Air Blank:  0.00

Calibration Test:  suppose to be between .074 and .086.  This number was below the allowed calibration under the regulations in some breath tests.

Air Blank:  0.00

Subject Test:  .135

Air Blank:  0.00

When the machine takes a breath sample, the air blanks are suppose to be zero, indicating the machine did not have any alcohol in the chamber before or after the test.  The breath test machine also conducts its own internal calibration on every test that is suppose to read .08.  Under the Massachusetts Regulations, the results are admissible if the calibration test is anywhere from .074 to .086, allowing for a .006 margin of error in the calibration test.

The Periodic Test of the Breath Test Machine

The officer in charge of the breath test is suppose to conduct a periodic test. This periodic testing is on a known solution of .08. The results should be within the same tolerance as on a subject test.

Office of Alcohol Testing Response to the out of calibration issue

In response to these problems, many district attorney’s office stopped using breath test evidence. All prosecutors began using the tests again around the middle of July 2015 as the Office of Alcohol Testing claimed that the problems were resolved and related to inadequate officer training.

In response to these issues, I filed a motion to discover how the Office of Alcohol Testing determine that the problem with the machine was related to officer training. Myself along with other lawyers made discovery requests to learn if the problem with the calibration went to the reliability of the machine or poor officer training as OAT claimed.  To read more about the background of the out of calibration issues, there was a helpful article by John Ellement and Evan Allan from the Boston Globe in April of 2015.

In response to this issue, the Office of Alcohol Testing released a CD claiming to show that it resolved the problems with the machine’s calibration.  This discovery response revealed that the Office of Alcohol Testing knew about this problem and did not bring it to the attention of the district attorney’s or defense lawyers.  Further, the responses revealed that numerous police departments were impacted by the machines being out of calibration.

The Office of Alcohol Testing stated that the out of calibration issue arose as a result of the officer not being trained to look to make sure the machine’s calibration is within the accepted range.  OAT claimed that the manufacturer allows for a wider tolerance than the Massachusetts regulations, which resulted in the machine failing to alert the operator of the errors in the calibration.

In response to the Office of Alcohol Testings claim to have resolved the issue, defense lawyers filed motions looking for certain documents, such as:

  • Communications between the Office of Alcohol Testing, District Attorney’s Offices and the Director of Transportation regarding the cause of the calibration issues;
  • Documents that the OAT reviewed to determine which test results were impacted by the out of tolerance issue.
  • Discovery of what efforts were made to discover how many tests were impacted by this error with the machine.

The request I filed detailed roughly 19 items that I believed were not provided by the CD that district attorneys provided in response to discovery requests.  It is anticipated that the Concord District Court consolidated hearing will address these issues.

Source Code Challenge and the Camblin Case

Also part of the consolidated hearing will be a challenge to the scientific reliability of the breath test machine. In a case that was decided on June 12, 2015, the Massachusetts SJC found that a judge committed error of law in not allowing a hearing to determine the scientific reliability of the breath test machine.

The Camblin Court found that the judge should have conducted an evidentiary hearing on the following three issues.

  1. Errors in the Computer source code that could make the breath test machine unreliable;
  2. Evidence that the breath test was not specific for alcohol and whether the fact that other compounds can be confused for ethanol by the machine make it unreliable.
  3. Whether the machine is properly conducting a calibration test prior to every breath test as required by the Code of Massachusetts Regulations.


This hearing will take place in Ayer District Court. Since the Alcotest 9510 is substantially similar to the 7110, the Court allowed defense motions to have a hearing and consolidated these issue with one judge.

It will take many months for these issue to resolve themselves with the first step an upcoming hearing in Concord on September 17th.

If you have questions on the Alcotest 9510 challenge, feel free to contact me and I will be happy to explain the issues before the Court.

To read more about breath test reliability issues, you can see my prior Blog posts on this topic.

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