If law-makers approach questions as a matter of common sense, the law should create criminal offenses when the behavior represents a danger to others. The threat of punishment is hoped to deter the unwanted behavior. The fact individual liberty has been sacrificed is justified because the safety of the many outweighs the loss suffered by the few who represent a danger. So when it comes to creating an offense affecting driving, the test is always going to be whether the driver was acting in a way that was inherently dangerous. Take as an example, someone who drinks alcohol or takes drugs which affect the ability to concentrate. If you know you will not be at your best but nevertheless drive, you are reckless you will lose concentration and have an accident. Voluntarily disabling your mind should not be a defense if you damage property or injure or, worse, kill someone.
An example from California
The California Office of Traffic Safety reports that 30% of all fatalities in car crashes tested positive for both legal and illegal drugs. Hence, Vehicle Code 23152a makes it an offense to drive any vehicle under the influence of alcohol, or drugs, or both, i.e. the quantity drunk or consumed affects the nervous system and impairs ordinary abilities to drive. So if the sober or drug-free driver would be driving safely, but you did not because of the alcohol and/or drugs, that represents the offense.
What’s the problem?
When it comes to alcohol, there’s a specific test for blood alcohol concentration. If your BAC is .08%, the offense is complete. The only way to test for drugs is through a blood or urine test, but there are no Californian standards for creating an offense based on particular levels of a drug. This means the test becomes more subjective, i.e. the arresting officer‘s judgement based on the driver’s:
• lack of control when driving, i.e. the reason for the stop;
• behavior when talking with the officer;
• general physical appearance;
• ability to perform the field sobriety test; and
• admissions made.
The law-makers also added in an offense to refuse a blood or urine test when reasonably required. To prove this offense, the officer requesting the test must be specifically trained to detect the symptoms of drug abuse
If drugs are found in the body, does this prove the offense of DUI Drugs?
Absolutely not. Let’s say the lab results show the presence of marijuana. This is not in any sense conclusive because this drug does not necessarily impair the brain function. Indeed some studies have shown levels of concentration can improve when the drug is first taken.
Worse from the prosecution’s point of view, the test only shows the marijuana was taken in the last three days. It does not prove you were impaired at the time of driving. If the chemical tests prove the presence of prescription drugs, the prosecution has the same difficulty of proving impairment. If you were legally using the drug and following the directions of your physician, you will have a reasonable chance of avoiding conviction.
All of which shows the general problems for law-makers when it comes to drafting laws to criminalize driving when prescription or illegal drugs are in the bloodstream. It all comes down to policy decisions about the extent to which they want to penalize drivers for their lifestyle when there may be a risk to the safety of other road users.