In recent years, the United States has made progress in reducing highway deaths through safer vehicles, roadway engineering, enhanced medical response, and data-driven enforcement tactics. However, crashes involving drug-impaired drivers continue to rise. According to a recent study by Columbia University, over 40 percent of drivers with past alcohol and cannabis use self-reported driving under the influence.¹

The research, unfortunately, doesn’t end there. Another study in 2020 by the National Highway Safety Administration illustrated the prevalence of injury and fatal crashes from hospital and medical examiner data in five metropolitan areas on the east coast of the United States. Data collected both before and during the COVID-19 pandemic exposed a significant increase of impairing substances, including 56 percent of drivers involved in serious injury and fatal crashes who tested positive for at least one drug.²

Since 2019, there has been a 44 percent increase in the number of fatalities involving an impaired driver in Colorado, where timely data were collected and reported in March 2022.³

This growing problem requires new strategies to be implemented to help turn this disturbing trend around and save countless lives. Law enforcement agencies can no longer continue to employ many of the same traditional approaches and expect different outcomes in the future.

Technology exists today to reliably detect drug-impaired drivers, which can help alter this dangerous trend and deter many from getting behind the wheel after consuming impairing substances that can affect their ability to operate a motor vehicle safely.

Oral fluid (saliva) drug testing technology is available now and is currently being used throughout the world, including in Spain, Canada, and Germany, as well as in multiple U.S. states, including Alabama, California, Illinois, Indiana, Michigan, and Wisconsin, among others.

Several available oral fluid testing instruments have demonstrated good efficacy and can screen for several common drugs of abuse. The Michigan State Police completed their second pilot phase using the SoToxa Oral Fluid Mobile Test System made by the healthcare company Abbott, which showed accuracy rates between 87 percent and 96 percent when compared to oral fluid confirmation samples.⁴  Indiana has also recently rolled out a statewide roadside oral fluid program using the SoToxa system.

Several other states across the country include roadside drug testing as a strategy in their respective strategic highway safety plans, including Colorado, Pennsylvania, and Wisconsin.⁵

Why Oral Fluid Testing?

Many law enforcement agencies deploy Drug Recognition Experts (DREs) who have specialized training to recognize impairment in drivers under the influence of drugs other than, or in addition to, alcohol. However, DREs represent only about 2 percent of all law enforcement officers in the United States.⁶

Even with more officers being trained in Advanced Roadside Impaired Driving Enforcement (ARIDE), we are still missing too many impaired drivers on our roadways.

Oral fluid testing can help detect the presence of a drug(s) when officers observe articulable facts and circumstances of impairment, which include the driver’s performance during sobriety tests and other general indicators. However, many of these signs can be dismissed due to drivers’ claims of medical problems, sleep deprivation, or inexperience. This is where roadside testing can add probable cause—to determine that the impairment is substance-induced and to allow for officers to have the operator further evaluated by certified DREs. This will only increase the demand to have DREs involved and help determine what is causing the impairment and what category(s) of drugs may be involved.

Think of a case where a driver has caused serious injury or death to another and may be injured themselves. Due to the circumstances, there might be the inability to conduct field sobriety tests and officers may make limited observations but have some reasonable suspicions. A roadside test may be the probable cause needed to move ahead in obtaining an evidentiary blood test and continue the investigation because the window of opportunity is too short to be able to obtain an evidentiary test later.

We cannot overstate the potential impact on deterring drug-impaired drivers from getting behind the wheel in the first place, especially if they know that law enforcement can drug test at roadside. This worked well for reducing alcohol-impaired driving with preliminary breath testing instruments utilized at roadside starting in the 1990s.

Some key benefits to a roadside drug testing instrument include

• • Portability for mobile deployment from almost any type of vehicle
  • Easy to use and rapid results within minutes
  • Minimally invasive (much more like a breath test)
  • Cut off levels are set to detect recent ingestion of drugs
  • Stored memory and users have the option to print the results at roadside

If possible, screening should be used in all impaired driving cases, even in instances of suspected alcohol, as there is high prevalence of alcohol combined with other substances among impaired drivers. Whether via a DUI court model or post adjudication, it is important to effectively treat the misuse of all substances and not have that individual in a position to re-offend.

It is important to also remember that the arrest decision should be based on facts and circumstances of impairment and not a positive drug test alone. For example, someone could test positive for a benzodiazepine that is prescribed, and he or she may not be impaired. All tests should be confirmed by a reputable laboratory.

Roadside oral fluid drug testing is reliable; nonetheless, though false positives and negatives could occur, as with any diagnostic test, which is why observable and articulable impairment is key. Additionally, oral fluid tests usually do not test for every substance, but rather the most commonly abused drugs that law enforcement tends to observe on the highway, such as amphetamine, benzodiazepines, cannabis (THC), cocaine, methamphetamine, and opiates.

Legal Precedence

In 2015, a judge in Kern County, California, ruled that the results of a roadside oral fluid testing device using lateral flow immunoassay technology were scientifically reliable, satisfying the Frye standard.⁷ Although this is one court, it does set a judicial precedence for future decisions.

If your state or jurisdiction does not allow for evidentiary or roadside oral fluid to be obtained, new legislation may be required to allow its use.

How to Start an Oral Fluid Program

Although the reliability of roadside drug testing has already been established, many agencies are still looking to start a pilot program to demonstrate proof of concept by collecting data from roadside testing instruments and comparing those results to evidentiary oral fluid or blood test results. It is important to make sure that the initiating party has the necessary authority obtained and that stakeholders understand that clear policy guidelines need to be established and followed.⁸ This will also likely require a voluntary consent form to collect the sample from the vehicle operator.

There are highway safety grants that can help fund equipment, and it may be possible for agencies to source funds for roadside oral fluid instruments and related costs through state highway safety offices or other means.

Lives lost and injured due to drug-impaired driving are unacceptable and preventable. Oral fluid testing should be a strong consideration as a strategy in combating impaired driving that can help in both prevention and enforcement.

Notes:

¹Priscilla D. Gonçalves et al., “Simultaneous Alcohol/Cannabis Use and Driving Under the Influence in the U.S.” American Journal of Preventative Medicine 62, no. 5 (May 2022): 661–669.

²National Highway Traffic Safety Administration, Update to Special Reports on Traffic Safety

During the COVID-19 Public Health Emergency: Fourth Quarter Data, Traffic Safety Facts, June 2021.

³Colorado Department of Transportation, “Combing Drugs and Alcohol Increases Risky Driving and Crashes: New State Data Shows Role of Impaired Driving in Record-Setting Traffic Fatalities,” news release, March 3, 2022.

⁴Michigan State Police, Oral Fluid Roadside Analysis Pilot Program – Phase II, 2021.

⁵Federal Highway Administration, “State Strategic Highway Safety Plan (SHSP),” January 21, 2021.

⁶International Association of Chiefs of Police, “States and Countries with DREs,” December 2021.

⁷State v. Salas, Case No. BF153631A (Cal. Kern Co., November 30, 2015, oral order).

⁸SOFT/AAFS Oral Fluid Committee, Oral Fluid Drug Testing Pilot Project Guidelines for DUI/D Investigations, 2020.