When people hear "DUI" they usually think of drunk driving. However, most states, including Arizona, have DUI laws that encompass many different types of impairment, including drug use.
Below, we've included a few points about how drugged driving is detected and punished under Arizona law.
Under Arizona's DUI law, it's illegal to drive under the influence of any drug that impairs one's abilities. That means that you can be charged with DUI for driving under the influence of even prescription or over-the-counter drugs if they impair your driving abilities.
With Breathalyzer units, it's easy for police to quickly determine whether a person has been driving while drunk. However, Breathalyzers don't detect drugs. So how can officer tell if a suspect has been drugged driving?
In short: there's no foolproof way to tell. For example, the marijuana metabolite THC can be detected in a person's urine or blood for up to five weeks. That window of time is too large to conclusively show that a driver smoked pot before driving, as opposed to smoking two weeks ago. Even the NHTSA admitted in a letter to Congress that current knowledge about drugs is too limited apply dosage limits to driving offenses.
In order to work around these limitations, 15 states, including Arizona, have passed "Per Se" drugged driving laws. These laws make it illegal to operate a motor vehicle with any detectable amount of certain drugs in your system.
That means that having any amount of a controlled substance in your system while driving in Arizona will get you the same DUI charge you'd receive if you were driving drunk. So that roach you may or may not have hit at that Phish concert last week could get you a DUI.