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Tests Used in California DUI Prosecutions


In the fight against drunk driving, law enforcement and lawmakers alike work tirelessly to implement new measures that will aid in DUI prosecutions. Many of these new measures are based on technological advancements, such as lasers to detect the presence of alcohol in the cabin air of a vehicle. As a driver in Orange County, it’s important to understand what technology may be used against you now and in the future. Read on to gain a basic understanding of the methods and tests being used and considered (for future use) in California DUI prosecutions.

Alcohol-Sensing Flashlights These special flashlights contain sensors that can detect the presence of alcohol on a driver's breath when used within about one foot of the driver. The flashlight can then indicate whether alcohol is present. Though the results of such a test are currently inadmissible as evidence in court, officers may use them to determine whether field sobriety tests should be performed.

Lasers Researchers in Poland released the results of a study that used a laser to detect alcohol in vehicle cabins. The laser is an off-site device placed on the side of the road and used to detect alcohol levels in passing vehicles. The data of such tests would be sent to waiting law enforcement officers down the road, who would pull over any potential drunk drivers to perform standard tests to determine possible intoxication.

Breath Tests A current standard in DUI testing, breathalyzer tests are used to measure the level of alcohol in a driver's breath. This type of device requires the driver to submit a breath sample by breathing into a tube. The device analyzes the breath sample for the presence of alcohol, calculating the driver's blood alcohol concentration (BAC). The results of breath tests are admissible in court and provide the foundation of the prosecution's case against a driver. These tests are widely used in DUI prosecutions across the country.

Blood Tests Considered more reliable than breath tests, blood tests require a blood sample from a driver that is then tested for alcohol levels. Blood samples must be drawn, handled and stored properly to preserve the accuracy of this type of evidence, which is admissible in court.

Mishandling or improper storage or testing of blood samples may render them unusable by the prosecution, making it important for a defense attorney to conduct an independent test and analysis of the manner in which such a sample was taken and handled. Like breath tests, blood tests are widely used in jurisdictions across the nation to prosecute DUI cases.

Ignition Interlock Devices Ignition Interlock Devices (IIDs) are installed in the vehicles of repeat DUI offenders to prevent future drunk driving. These are small breath test devices that do not allow a vehicle to start if a driver submits a sample tainted with alcohol. A breath sample is required to start the vehicle and is also required at intervals while the vehicle is in motion. If a driver fails to provide an alcohol-free breath sample while the vehicle is in motion, the horn may honk and lights may flash to alert law enforcement.

Anti-DUI Devices in New Vehicles There is new technology being considered to prevent drunk driving in the first place. Concept cars have been presented that include sensors in the cabin, which would be used to detect a driver's BAC and would prevent the vehicle from starting if it is .08% or greater. One system in such a vehicle uses a touch-sensitive sensor in the steering wheel and an infrared light. The other tests the driver's breath using cabin air rather than requiring the driver to breathe into a tube or other device.

Fighting DUI charges is not easy, particularly as new technology is implemented to provide law enforcement with new methods to make arrests and gather evidence against suspected drunk drivers. At the Law Offices of Virginia L. Landry, Inc., we take care to stay on top of the latest technology and DUI laws. Our firm represents drivers in Orange County who have been arrested for and charged with drunk and drugged driving.

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