As with any type of technology there are a variety of legal concerns and challenges that are raised in court regarding the use and reliability of alcohol interlocks. This is commonplace and it is expected that a variety of concerns in relation to the use of these devices and other technologies will continue to be raised in the courts in the future.
Legal challenges that are commonly raised by the defence often involve alternate explanations for alcohol-positive readings. Essentially, the defence attempts to develop plausible reasons for alcohol-positive readings captured by the device that may assist the offender in avoiding additional sanctions. Alternate explanations often relate to how alcohol is metabolized by the body, mouth alcohol, the way that foods can produce positive readings, and other drivers that are responsible for alcohol-positive readings. In these instances, it is important that the court select an objective and unbiased expert witness who is able to address these challenges and provide evidence and testimony that meets court rules of evidence.
The defence may also endeavour to provide the program authority with reasons to excuse the offender from participating in the alcohol interlock program. These reasons may relate to the inconvenience the device may pose for family members, the ability of the offender to provide an adequate breath sample, cost, and indigency.
Such challenges relating to the device or the application of the device to an offender can be easily refuted with the availability of good information.