Every driver knows that it’s illegal to drive under the influence of alcohol. Likewise, it’s illegal to drive under the influence of drugs like marijuana or methamphetamine. This doesn’t mean that it never happens, of course, but simply that people are aware that it is a violation of the law.
What may surprise them is to find out that they could still qualify as driving under the influence if they’ve been using some prescription drugs. They could end up facing charges, even though it was legal for them to have those drugs and to use them – and even though the driver themselves felt that they needed to use that medication to deal with whatever ailments they were facing.
Impairment vs.”per se” impairment
One thing to understand is that there are two types of DUI charges, as a general rule. The first is known as per se impairment, and it happens when a driver has consumed enough alcohol that their blood alcohol concentration exceeds the legal limit. For most drivers, this is 0.08%. The driver can argue that they were not impaired, but they can still be charged with per se impairment simply for having violated that limit.
Generalized impairment, however, can be charged even if someone’s BAC isn’t over the legal limit. This is why someone can exhibit signs of impairment at 0.07% and still get a DUI. It’s also why you can get a DUI if you’re under the influence of other drugs or medications that wouldn’t show up on that breath test. You can still qualify as being impaired based on the substances that you took, and you could face charges if the police decide to make an arrest.
These cases can become far more complicated than standard DUI arrests, so you need to know about all of your legal options.