If someone has been pulled over, arrested and charged with driving under the influence, their case could be more complicated than it initially seems. A growing portion of the American population relies on prescription drugs to live a happy, healthy life. Most people, however, do not imagine that prescription drug use could affect their everyday capabilities, such as driving.
And now the legal system is faced with handling the effect that such drugs are allegedly having on people behind the wheel. In some cases, drivers who are charged with a DUI are unfairly accused due to the presence of legal prescription drugs in their systems. According to sources, most states are effectively able to measure the amount of alcohol in a person's system, but such a measurement doesn't really exist for testing for prescription drugs.
Because the legal system treats impairment equally, no matter whether a driver is impaired by alcohol or drugs, suspects accused of DUIs are put at risk in the legal process. Since no valid testing exists to determine illegal levels of impairment due to prescription drugs, courts are left making decisions based on no set system. For example, if a blood or Breathalyzer test reflects that a driver's BAC measures at .08, the legal system specifically determines that the driver has broken the law.
The lack of such tests regarding prescription drugs sometimes leads to courts dropping DUI charges, which is the correct course of action as long as no dependable system is in place to determine prescription-drug related impairment. It is not a reasonable standard to merely charge someone with a DUI because he or she appears to be impaired. That process leaves too much room for individual interpretation that would result in reckless DUI charges.
USA Today: "DUIs involving prescription drugs difficult to prove," Kaustuv Basu, 18 Oct. 2010