While getting paid to drive stoned and drunk might seem like a poor decision, the 18 individuals who did just that were following the high calling of science.

The study was conducted by the National Institute on Drug Abuse and was designed to investigate the effects marijuana had on driving.

Currently, scientists are hazy about exactly how marijuana affects driving ability, a topic of ever growing importance as more and more states reduce their restrictions on the drug, for both medical and leisure purposes.

To do this, the study gave participants a small amount of alcohol, pot, or a placebo, and had them get into the University of Iowa’s National Advanced Driving Simulator.

The simulator is a 1996 Malibu sedan set inside a 360-degree dome, and it allows researchers to study the differences each substance had on driving ability.

The study found that lane weaving increases when participants used both alcohol and marijuana. However, taking both drugs together did not double the effect of either one.

“What we found is the effects were additive,” said Marilyn Huestis, the chief of chemistry and drug metabolism at the National Institute on Drug Abuse and the  primary investigator of the study. “So whatever effect cannabis had were added on top of the effects that alcohol had.”

In addition, while alcohol changed the number of times the car veered out of the lane and the speed of the weaving, marijuana didn’t. However, marijuana did show an increase in the amount of weaving.

Andrew Spurgin, a UI pharmacy research fellow and a coauthor of the study, said they were somewhat surprised by the results of the combination of alcohol and cannabis.

“We originally thought it would be a synergistic-type effect when cannabis and alcohol were [both] administered,” he said. “What we found was more of an additive effect, an A plus B effect.” When taking both alcohol and cannabis together, instead of doubling the effect of the drugs, it only added on to the effects each drug independently had on weaving in a lane while driving.

The study also found that the primary psychoactive drug in cannabis is equivalent to a blood-alcohol concentration of .08. However, testing drivers under the influence of cannabis may not provide accurate results.

The researchers are also trying to figure out a more precise method of determining how high a person is.

Scientists know that 13.1 anagrams per milliliter of THC (the main intoxicant in marijuana) is equivalent to blood-alcohol concentration of 0.08. The problem however, is that THC behaves differently in the body than alcohol.

“In the United States, it takes between 90 minutes and four hours to get the blood sample drawn,” Huestis said. “So that 13.1 decreases tremendously after that time point, and we’re working on that now to try to determine how much that drops over time.”

Huestis hopes that the study will help policymakers make more educated decisions on alcohol and cannabis legislation.

A staunch supporter of legalized medical marijuana, Sen. Joe Bolkcom, D-Iowa City, said he does not believe this study will negatively affect future bills on marijuana because it focuses on driving under the influence.

“I continue to support responsible medical care to help those Iowans who suffer everyday chronic conditions that simply aren’t getting their needs met by conventional medicine,” he said. “However, I don’t think people should drive while they’ve been under the influence [of cannabis or alcohol.]”  Bolkcom also criticized the double standard surrounding alcohol legalization.

“We have very strict laws around driving and drinking, but we don’t outlaw alcohol for everybody because some people drink and drive,” he said.

“We should find a responsible way to provide safe and legal access to medical cannabis for suffering Iowans.”