Tolerance and DUI/Drugs
When I began my career as a DUI defense attorney in Beverly Hills sixteen years ago, it was uncommon for people to be arrested for driving under the influence of medications only. Although the majority of DUI cases are still based on alcohol, DUI arrests based on drugs, including prescribed medication are becoming more and more common. Partly, I think this is a product of the availabilty of drugs and the willingness of doctors to hand out prescriptions for medications without any consideration for how the drugs may impair a person's ability to drive. It is also a result of the increasing awareness of law enforcement agencies to the problem of people driving while impaired through medication. Many prosecuting agencies now have deputies specially assigned to deal with this problem.
One issue common to all DUI cases based on prescriptive medication is tolerance. That is, how long has the defendant been taking the medication and how tolerant to the medication is he/she. Medication tends to effect people in very different ways. Some people may have a significant reaction to medication such that even small doses may impair them. On the other hand, people who have been taking a medication for years may have a high tolerance such that high doses may not impair them at all. It is not uncommon for defendants to be utterly confounded by a DUI prosecution based on medication, when they have been taking the medication and driving with it in their system for years. Often, no doctor has given any meaningful advice to the defendant as to how the medication may impact their driving. Of course, the doctor's or defendant's opinion concerning the effects of the medication mean little to a prosecutor who is presented by a report from a drug recognition expert stating that the suspect was impaired at the time of driving and giving details supporting the opinion.
These cases often go to trial as there is no bright line above which a defendant is presumed to be impaired. It is all a matter of opinion. The defendant will have his/her opinion, the arresting officer or drug recognition expert will have a different opinion. What matters ultimately is the opinion of the members of the jury.