The Hawaii Supreme Court has overturned the conviction of a Hawaii island medical marijuana user who was found with a small amount of cannabis at Kona Airport.

Geoffrey Woodall had a valid medical marijuana certificate but was still convicted under state laws for the two grams of marijuana discovered when he went through airport security screening.

In a 4-1 ruling Friday, the justices held that a conflict in state laws on the issue must be resolved in favor of Woodhall.

The majority said he must be acquitted.

The ruling suggests that a person holding a medical marijuana certificate can transport a small amount of cannabis at an airport for medical use.

But it stopped short of saying medical marijuana users can possess the substance at other locations, such as their workplaces, schools and public parks and beaches.

The court also noted that a medical marijuana user can still be prosecuted under federal laws that do not recognize any acceptable medical use for cannabis.

Federal laws apply at airports.

Deputy Public Defender Kirsha Durante said she and Woodhall are pleased with the ruling.

She said it affirms that medical marijuana users with valid certificates have a defense to state marijuana laws, but added that the narrow ruling makes clear that the defense must establish certain conditions.

Those conditions as outlined by the court include the amount must be under the three-ounce medical marijuana limit, the cannabis cannot be used or carried in open view and the marijuana is being transported for medical use.

The majority’s 30-page ruling was written by Associate Justice Sabrina McKenna. Chief Justice Mark Recktenwald agreed with part of the majority but said he would have upheld the conviction.

Woodhall was going to Oahu when he was arrested March 8, 2010, after the marijuana was found in a plastic bag. He had a valid Medical Marijuana Registry Patient Identification Certificate.

He was convicted, fined $50 and ordered to pay $280 in fees. The sentence was stayed pending the appeal.

The majority pointed to a conflict between one state law that allows transportation of medical marijuana and another that prohibits transporting it through “any place open to the public.”

The airport fell under “any place open to the public.”

The justices held that the “irreconcilable conflict” must be resolved in Woodhall’s favor under the “rule of lenity” that holds that ambiguities in the laws must be interpreted against the prosecution and in favor of the defendant.

The majority said it was not addressing the prohibition law’s other provisions banning medical marijuana at locations that include schools, school and public buses, moving vehicles, workplaces and public parks and beaches.