The state Supreme Court has ruled that the presence of non-impairing marijuana compounds detected in a person's body does not give authorities the right to prosecute under Arizona's driving under the influence laws.
Last year, the state Court of Appeals upheld the right of authorities to prosecute pot smokers for DUI even when there is no evidence of impairment.
"I think that what the court has done here is they applied common sense to a ruling regarding [DUI laws]," said J.P. Holyoak, a medical marijuana card holder.
Holyoak says driving days after using medical marijuana is a concern for many who use the drug.
"There is always the thought that if the courts obtain a warrant and they're able to draw your blood, it would test positive [for inactive metabolites] and then you could be charged with DUI even though you weren't impaired in any way, shape or form," he said.
The Supreme Court opinion released Tuesday notes that while Arizona statute makes it illegal for a driver to be impaired by marijuana use, the presence of a non-psychoactive compound does not constitute impairment under the law.
"Up until now, the way the law is interpreted, you can get a DUI even if you're not impaired and all you have is the secondary inactive metabolite in your body," explained Michael Alarid III, an attorney with the Law Offices of David Michael Cantor.
Alarid represented Hrach Shilgevorkyan, the petitioner in the case that faced the state Supreme Court.
"It's a big deal because it's a change in the law. It should never have been a crime in the first place," said Alarid.
The opinion focuses on two chemical compounds in marijuana that show up in blood and urine tests - one that causes impairment and one that stays in the consumer's systems for weeks but doesn't cause impairment.
Maricopa County Attorney Bill Montgomery issued the following statement in the wake of the opinion:
"The only way the Court could reach its holding was by creating ambiguity where it did not exist in order to engage in interpretive jujitsu and impede on a function specifically left to the legislature: changing a clearly worded statute to accommodate changes in circumstances if called for. A healthy respect for our tripartite system of state government sometimes means restraint by one branch of government where invited to act and resisting the temptation to do so.
"By acting as it has, our State Supreme Court contributes to citizen cynicism particularly when it involves the whys and wherefores of drafting and passing legislation. Why should citizens work through our republican form of government and petition their duly elected legislators for statutory change when they can take a shot at only having to persuade just three Justices? Instead, the Court should have directed relief to the appropriate branch of government: the legislature."
Copyright 2014 Associated Press. All rights reserved. CBS 5 (KPHO Broadcasting Corporation) contributed to this report.