How Alcohol Breath Sensor Devices Work

I have written previously on this blog about on-going litigation between DUI lawyers in various states and the manufacturer of the Intoxilyzer 5000 and other alcohol breath sensor equipment.  At issue is the source code of these machines, which DUI defense counsel is calibrated to measure an average sized man.    The machines take no account of different sized individuals or possible differences in alcohol metabolism in females.

The manufacturer does not want to release its source code, claiming that this information is a valuable business trade secret.  Defense lawyers argue that if this equipment is used to convict their clients then they have a right to see the source code.

Georgia trial courts have not given us a definitive answer.   Georgia DUI lawyer George Creal cites a recent case on his blog – Holowiak v. State, where the Court of Appeals sidestepped the issue but refused to order CMI (the manufacturer of the Intoxilyzer 5000) to reveal its source code.

In any case, you may be wondering how these machines work in a general sense.  The well known web site “How Stuff Works” has a easily understandable and thorough explanation entitled How Breathalyzers Work.   If you and your lawyer plan to challenge a DUI charge by attacking the technology of the equipment used to determine blood alcohol levels, the How Stuff Works article is a good starting point for your research.