The Office of Alcohol Testing within the Massachusetts State Police Crime Laboratory certifies all breathalyzers used in Massachusetts drunk driving cases. Each breathalyzer certification is valid for one year and any breath test which is conducted by an uncertified breathalyzer is invalid and inadmissible. The admissibility of Breathalyzer certifications without live are is currently being challenged on the grounds that admissibility of such certifications violates the confrontation clause of the Constitution. This challenge is based on the Supreme Court case of Melendez-Diaz v. Massachusetts. 

The Massachusetts Office of Alcohol testing has promulgated a detailed set of regulations which must be followed in order to admit blood alcohol results from DUI breathalyzer or blood tests. Any violation of the Massachusetts blood or breath testing regulations will likely result in suppression of the blood alcohol content-related evidence.

Massachusetts DUI lawyers have been able to successfully challenge BAC-related evidence where the police officer conducting the Wayland MA alcohol breathalyzer test was not properly trained, tested, and certified. DUI lawyers can also challenge breath test results where the breathalyzer or simulator unit used in a drunk driving case was not recertified by the Mass. Office of Alcohol Testing within allowable time limits.

Also, for a breathalyzer test to be valid, the police must keep the DUI defendant under continuous visual observation for 15 minutes prior to the administration of the breathalyzer, to insure that the person arrested for drunk driving has not belched, hiccoughed, or ingested anything by mouth. This is because contamination of the breath sample can produce artificially high BAC readings.

Breathalyzers used in Massachusetts operating under the influence prosecutions use a simulator solution. This is a solution which is produced in a laboratory which has been tested with an alcohol content of .15. For Wayland Mass blood alcohol level breath test results to be admissible, the simulator solution must register at .14, .15, or .16 at the time of the breath test. This is called a calibration standard analysis. Like the breathalyzer, the simulator solution must also be certified. Rules regarding the storage, handling and periodic replacement of breathalyzer simulator solution must also be followed.

A comprehensive set of rules also govern the collection, handling, and storage of blood in Massachusetts drunk driving cases. Wayland MA DUI blood alcohol test results, like breathalyzer results, can be suppressed and excluded from trial if the procedures are not followed. 

Also, a number of studies found chemicals and substances other than ethanol can interfere with infrared breath testing devices and produce inaccurate readings.

Alcohol trapped in the test subject's mouth can account for artificially high blood alcohol readings. These high readings occur because the breath testing equipment is designed to measure deep lung air and not alcohol in a person's mouth which is blown directly into the breathalyzer. Mouth alcohol has found to be the most common cause of false breathalyzer readings.

Preliminary breath testers (PBTs) are portable electronic devices which are used in Massachusetts DUI cases to measure alcohol present in a driver's breath. They are only roadside screening devices and their readings cannot be used in a Mass. DUI trial to prove a defendant's alcohol level. Preliminary breath test results may be admissible at a pretrial motion to suppress evidence where a lack of probable cause is claimed. However, PBT alcoohol readings cannot be admitted at trial.  

DUI Attorneys McCarthy, Simoneau, and Watkins are intimately familiar with the blood alcohol admissibility requirements. With their in-depth knowledge, it is possible to win a DUI case even if the defendant has taken a breathalyzer or blood test. In cases where procedures are not followed or there is evidence that the breathalyzer was not functioning properly, breath test results can be excluded.