Mens Rea- Breath Testing gets a second look

Breath test instruments have not been shown to be reliable. Their reliability to prove criminal charges

is accepted on faith.

In Pennsylvania, attorney Justin McShane put breath testing to the test. It was examined by a district court judge who was a former state police trooper in Commonweath v Schildt, and the trooper-turned judge found that the lack of a ''linear dynamic range'' in the calibration of the breath test instruments used in their cases did not pass scientific muster and the results were deemed inadmissible.

The essence of the issue was the failure of the breath test instrument used in Pennsylvania to be calibrated along the linear curve at values that are relevant to prove a specific ''per se'' charge based on a measured breath alcohol content.

McShane says the linear dynamic range is like the boundaries for a football field: ''if the receiver catches the ball out of bounds, it's not a touchdown''--even if the receiver catches the ball and the ball is over the goal line.

McShane developed this challenge over several years. He used an infrared spectroscopist, an expert in measurement and a toxicologist, to explain to the judge the need to demonstrate accuracy through rigorous calibrations along a sufficient number of values on a linear curve. The amazing and really admirable thing about McShane's success in this case is that a court considered an argument questioning the reliability of an evidence gathering tool that has been accepted since the 1950's.

When Delta Airlines grounded the ''dreamliner'' it was not because any passengers were killed or injured in a crash. The reason is the question raised about the performance of a new battery used to help power this super-sized bird. Even though air travel has been accepted for longer than breath testing for alcohol, questions were raised about how this new battery developed from new technology would perform: was the testing rigorous enough? What did the data show? Was it able to perform under various conditions and hypotheticals? There were problems revealed when the battery was performance-tested under several different scenarios for the Federal Aviation Administration (FAA), which could expose passengers to risk.

Millions of dollars were spent on this new plane. The experiments and testing on this device had serious implications. The airline needed the component parts to receive approval to get this new plane in the air carrying passengers and generating revenue for its board members. Therein lies the rub: the airline's business is making money by flying passengers. There are human lives in that craft. If something goes wrong and the plane goes down - the airline is going to have questions to answer and one of the first questions would be about the testing of that new battery.

Scrutiny finally is starting to be applied to breath test instruments that are used to prove a bodily alcohol level in drunk driving prosecutions. It is absolutely appropriate. After all, human lives are at stake. Once you are convicted of a drunk driving charge in Michigan, you are convicted for life. There is no provision under the law to allow someone to ''expunge'' a drunk driving conviction. You may lose a job, a security clearance, a promotion --a future.

Scientific scrutiny led to an incredible result in Pennsylvania that may mean breath testing is no longer accepted there. We have science to thank. Breath testing, if it is continued or reinstated, should be a more rigorously tested and better understood form of evidence gathering with the limits to its accuracy embraced by the prosecutors, judges, defense attorneys and jurors.

Mike Nichols is an East Lansing criminal defense attorney who focuses on defending those charged with DUI-DUID. He is sustaining member and Michigan delegate for the National College for DUI Defense,.a founder and the secretary of the Michigan Association of OWI Attorneys, and an associate member of the American Academy of Forensic Sciences and the American Chemical Society. He can be reached at mnichols@

Published: Thu, Apr 18, 2013