Skip navigation
The Habeas Citebook Ineffective Counsel - Header
× You have 2 more free articles available this month. Subscribe today.

The Faulty Science of Breathalyzers

by Jayson Hawkins 

The forensic sciences, once believed to offer infallible evidence against a wide spectrum of crimes, have in many instances been exposed as little more than smoke and mirrors. 

To the growing list of faulty, misleading, or disproven methods can be added alcohol breath-testing.

A recent investigation by The New York Times has exposed the supposedly scientific devices that conduct the tests to often be unreliable at best; at worst, they are generators of bogus results that have condemned untold number of drivers to undeserved criminal convictions. 

According to the Times, there are a million drunk-driving arrests annually in the U.S. While they often begin with an impairment test such as balancing on one foot, they almost always end with blowing into a black box meant to measure the percentage of alcohol in the driver’s system. If the machine spits out an estimate greater than or equal to 0.08, the driver’s luck is about the take a downward turn. 

The seeming conclusiveness of a breath-alcohol reading discourages anyone from fighting the result in court. The best option is often pleading guilty for a reduced sentence or to avoid jail time even when the accused know they are innocent. As the Times puts it, “When it’s the state armed with fake science vs. an individual motorist who had a couple of beers, everyone knows who wins.” 

Massachusetts, a state whose forensic laboratory already had a reputation for committing fraud, found that its lab had no procedure to test the Alcotest 9510 machines currently in use—and that technicians had covered up hundreds of unsuccessful attempts to calibrate the machines. The problems ran so deep that the state’s courts have discarded over 36,000 test results and halted use of the machines until significant reforms are made. 

New Jersey has experienced a similar crisis wherein 13,000 cases have had to be overturned because of programming errors in the Alcotest 7110. Although the manufacturer, Drager, fixed the software when experts pointed to the problems in 2007, the state neglected to implement the update. 

Washington state also ran into trouble with Drager products, including the 9510 model that sometimes rounded up results to push drivers past the .08% threshold.

Issues in other states have made it clear that problems with breath-alcohol test devices are not limited to a single manufacturer. Vermont discovered that Intoxilyzer BODO machines were consistently unreliable as early as 2005, yet Florida, Mississippi, Oregon, Ohio, and other states have continued to use them. 

The problem, in a nutshell, is that the only valid means of determining blood-alcohol content is through a blood test—a particularly invasive procedure that law enforcement should neither be expected nor trusted to perform.

Rather than base arrests on the amount of a substance in one’s blood, then, the Times points out that the logical solution would be to predicate them on reckless driving. 

If the growing list of faulty forensics has taught but one lesson, it should be the inherent danger in mixing political power with pseudoscience. As the Times report concludes, “The state cannot be trusted to police its own application of science in service of itself. It will always face an incentive to exaggerate to gain more money and more convictions.” 



As a digital subscriber to Criminal Legal News, you can access full text and downloads for this and other premium content.

Subscribe today

Already a subscriber? Login



CLN Subscribe Now Ad 450x600
Advertise Here 4th Ad
Stop Prison Profiteering Campaign Ad 2