Yes you can get a DUI from smoking and driving. The officer will check to see if the car smells like marijuana and if it does, they may pull you out of the vehicle and administer field sobriety tests. They will closely examine your personal demeanor and monitor your behaviors to see if you exhibit any telling signs. You will be given a DUI that is extremely hard to contest in court.
Driving under the influence of marijuana, alcohol, or a combination is a crime in Hawaii. A driver is under the influence when the drug, alcohol, or combination impairs the person’s ability to operate a vehicle in a careful and prudent manner. Also, while Hawaii allows medical marijuana use under limited circumstances, it is still a crime to drive after such use if the driver’s mental or physical faculties are impaired.
You may be tested chemically by urine or blood samples.
Yes, you can definitely get a DUI in Hawaii. And among the cops there are DREs, aka drug recognition experts, with their methods to clearly see when you are high. The level of THC in your body would be determined by an urine test or a blood test, but nevertheless you are going to be in a big trouble, since you smoked weed which is illegal in Hawaii, plus you were driving under influence.