According to the National Highway Traffic Safety Administration, driving under the influence of marijuana and other drugs is on the rise in the United States, as well as the number of fatal crashes caused by drivers impaired by drugs.

The Center for Emergency Management and Homeland Security at Arizona State University is addressing this growing public health and safety threat with a new app aimed at giving both drivers and law enforcement an easy way to detect impairment. Download Full Image

The center, part of ASU's College of Public Service and Community Solutions, is collaborating with researchers at SUNY-Downstate Medical Center, Barrow Neurological Institute and the Center for Cognitive Ubiquitous Computing to create an application that can be downloaded to a smartphone or tablet computer and allows users to check for impairment in the hopes they will be persuaded not to get behind the wheel.

Another collaborative project focuses on having law enforcement use the app in the field to detect what drug is in a person’s system and the degree of impairment, beginning with marijuana.

Leveraging technology in new ways

“It’s a noninvasive test that employs a proven technology that is currently being used to diagnose neurological disease,” said Richard Dale, executive director of the Center for Emergency Management and Homeland Security.

Dale said the technology differs from the horizontal gaze nystagmus test, or HGN test, which detects jerking movement when a person’s eyes follow an object side to side, a well-recognized field test that law enforcement uses in suspected driver impairment stops.

“The technology is being used to detect Alzheimer’s or Parkinson’s," he said. "Because of its accuracy, it’s a technology being adapted by the United States Marine Corps to train their Apache attack helicopter pilots.”

Our eyes must constantly scan the environment to form a mental picture of the surroundings. These rapid movements are called saccades or micro-saccades. Analysis of these movements – the velocity, direction and angle – can be used to reveal chronic or temporary brain impairment.

When eye motions are affected by alcohol or drugs, the failure to scan for changes in the field of vision can interfere with a driver’s ability to make decisions and react quickly.

The center is working toward funding the next phase of development to build out the pilot project. That includes creating biomarkers for the most commonly used illicit and prescription drugs that cause impaired driving.

Field sobriety tests help law enforcement determine if a driver is impaired, but officers don’t have a timely way to definitively confirm which drug is causing impairment. If blood is drawn, results may not be available for days. And courts have found many blood tests on those suspected of marijuana impairment to be inadequate.

Ultimately, researchers aim to correlate saccadic eye movement to specific medications and drugs.

“All the pieces are in place, and this is an ideal time to move this technology into greater use,” Dale said. “We are talking to potential partners to help us take the next step.”

Addressing a public safety concern

As more states allow the recreational and medicinal use of marijuana, there is growing concern about people endangering their own life and the lives of others by driving impaired.

In Colorado, where marijuana use is legal, 12 percent of DUI citations in 2014 involved suspected marijuana use. A study found that despite a decline in fatal crashes in 2011, the number of fatal crashes in Colorado in which drivers tested positive for marijuana went from 5.9 percent in 2009 to 10 percent in 2011.

“This is a public health issue, and often victims are innocent, non-impaired people,” Dale said.

New studies published by the National Highway Traffic Safety Administration shed light on the extent of the problem.

A national survey of 9,000 nighttime weekend drivers found that while alcohol use continues to decline, the percentage of drivers testing positive for illegal and legal drugs went up from 16.3 percent in 2007 to 20 percent last year. Overall, studies found those under the influence of marijuana had a 25 percent higher risk of crashing.

“On the roadways we’re much more worried about the potential of an individual being affected by the drug [marijuana] and the resulting impairment,” said Richard Besserman, an operations executive with the ASU Center for Emergency Management and Homeland Security, who brings over 25 years of experience as a surgical specialist, and more than 15 years as an executive in bioengineering and software development.

“It is about awareness, education and deterrence,” he added. “Similar to breathalyzers and alcohol, this technology has the potential to be just as useful to individuals, law enforcement and the judicial community.”