Understanding Breathalyzers

Florida, in addition to every other state, uses breath test devices to gauge whether or not a driver is intoxicated and, if so, to what degree. All 50 states have set the level at which the state presumes a driver is impaired (thus making driving in that condition a criminal offense) at 0.08 percent blood alcohol concentration, say Broward DUI attorney William Moore. Many, if not most, people are familiar with that particular component of the drunk driving statute, due largely to the campaigns waged by private organizations and law enforcement agencies against driving under the influence of alcohol. There is another provision, however, under which a motorist can be convicted of DUI: if he or she is actually impaired. For example, a person whose BAC, as determined by a breath test device, is only 0.05 percent can be arrested and convicted of DUI if there is other evidence to demonstrate impairment. According to Fort Lauderdale drunk driving lawyer William Moore Criminal Defense, the other evidence could take the form of testimony by a police officer or sheriff’s deputy regarding the motorist’s performance in roadside field sobriety tests, nystagmus tests on the eyes, slurred speech, and other symptoms of intoxication.
Breathalyzer results are important to the state’s case when prosecuting a DUI case. It is the only crime for which a criminal defendant can be convicted solely on the basis of the results of a mechanical device. There are a myriad of problems associated with breath test devices. They can be unreliable for a host of reasons, says Fort Lauderdale DUI Lawyer William Moore. For example, the devices are calibrated for an “average” person, one whose lung capacity is within that range, and is likely less reliable the farther from that “average” size a person taking the test actually is.
Additionally, some DUI lawyers believe that there is a confrontation problem. The manufacturer of the breath test equipment, a company called CMI, Incorporated, has refused to release the source code for the Intoxilyzer device. The source code is the computer coding that tells the machine what calculations to run. Because a DUI defendant cannot argue against the way the calculations are made, there is an analogy to being unable to confront an adverse witness.
A driver must generally submit to giving samples, including breath samples, for testing when he or she is under suspicion for driving under the influence. This is called implied consent and refers to the legal doctrine that a driver has already implicitly consented to providing samples by driving on Florida roadways or holding a Florida driver’s license.


Fort Lauderdale DUI attorney William Moore provides outstanding DUI defense in Broward, Fort Lauderdale, and Fort Lauderdale-Dade Counties. If you have been charged with a DUI, contact Fort Lauderdale DUI Lawyer William Moore, P.A.
This article should be used for informational purposes only and should not be construed as legal advice nor as implied representation of any person.
Article contributed by Mallory Shipman, Esq.