Driving Under the Influence: What is Impaired Driving?

Driving under the influence, driving while intoxicated, operating while intoxicated, operating a vehicle while intoxicated, driving while ability impaired, operating under the influence — these terms and their associated acronyms (DUI, DWI, OWI, OVI, DWAI, OUI) all have similar meanings. You may think you grasp it, but do you know what it actually means to be intoxicated, under the influence of a substance, or to have impaired driving ability?

Each state has its own definitions for “intoxicated” and “impaired.” Let’s break down three causes of impaired driving.

Drunk Driving: Impaired by Alcohol

When most people think of impaired driving, they imagine alcohol-related driving offenses. Each state sets the blood alcohol content limits for what is considered impaired. For example, Utah allows .05 percent BAC, while all other states allow .08 percent BAC before charging a driver 21 or over with DUI.

If you’re pulled over for suspected drunk driving, or in an accident suspected to be caused by drunk driving, you will likely be given a field test if you’re able. If you fail the field test, you may be required to take a blood alcohol test or breath alcohol content test (BrAC), which is commonly referred to as a breathalyzer. 

Passing the test doesn’t necessarily mean you won’t be arrested. In some states, you can still be arrested if your driving ability is impaired, even if your BAC is within the legal limit. This is true in situations where the driver is under 21 - in those cases, any presence of alcohol is considered under the influence. Additionally, if alcohol is detected and you’re driving recklessly, your state may pursue a DUI charge.

The Supreme Court ruled you can also  be charged with drunk driving if you are in the driver’s seat, even if the car is parked. This is even true in cases where the driver is unconscious or asleep, as decided in Mitchell vs. Wisconsin. This is because you are impaired while having physical control over the vehicle. 

Drug-based Driving Offenses: Impaired by Drugs or Medication

You will be arrested for a DUI if you are caught driving under the influence of drugs that impair driving ability, you can be charged whether the drugs were legally prescribed, over-the-counter, or illegal drugs. 

Legal Drugs, Illegal Impairment: Prescription Medications or OTC Drugs

Check the side effects of over the counter and prescription medication. They should read label warnings of potential side effects, and take note if they include a warning about drowsiness or operating heavy machinery. Side effects of both over-the-counter and prescription medications might include blurred vision, nausea, drowsiness, or dizziness. If you’re taking a new drug, you shouldn’t operate a vehicle until you know how it will impact your driving. If you find that it does impair your ability to drive safely, make other arrangements. If you’re not sure, talk to your pharmacist about your medications.

Dangerous Combination: Mixing Drugs and Alcohol

A recent study from NHTSA showed that more drivers are using alcohol in combination with other drugs, like THC. Active THC was more prevalent among drivers after COVID hit in 2020  (32.7% versus 28.3%), and opioid use among drivers nearly doubled from 7.5% to 13.9% during the same period. 

Combining alcohol and drugs or using two or more drugs can amplify their effects and increase impairment. You should ask your pharmacist before combining medications. . Every state has different laws concerning drugged driving. Stay safe, to avoid arrest or a serious accident. 

Driving while High: Legal or Illegal Marijuana

National Roadside Surveys show that aside from alcohol, marijuana is one of the most common drugs found in drivers’ systems. These surveys were conducted roadside and data comes directly from drivers. Between 2007 and 2014, the number of drivers in the sample population who had THC in their systems increased from 8.6 percent to 12.6 percent. This seems small, but it actually represents a 48 percent increase in the likelihood of drivers testing positive for THC in just 7 years. This may be in part because marijuana is now legal in several states. But just like alcohol, even though it’s legal, it’s still illegal to drive under the influence. Each state sets limits for THC concentration  in your system. 

NHTSA studies show marijuanaslows your reaction time, impairs your executive functions, and interferes with routine planning, decision-making, and risk-taking, causes problems with road tracking (lane position), and decreases your attention span. This puts you, your passengers and other drivers on the road at risk.

Drowsy Driving: Impaired by Sleep Deprivation

Drowsy driving can be just as dangerous as drunk and drugged driving, yet it’s more difficult to regulate and detect. Did you know the following statistics? Safety.com reports several alarming facts about drowsy driving, such as: 

• Staying awake for 20 hours or more leaves you as impaired as if your blood alcohol limit of .08 percent drivers cause more than 100,000 accidents each year. 
• During just 4-5 seconds of micro-sleep, you can drive the length of a football field.
• These statistics show just how many people are impacted by drowsy driving, and how quickly things can go wrong on the road. 

The CDC also states that you’re more likely to drive drowsy if you:

• Regularly do not get enough sleep  
• Are a commercial driver
• Are a shift worker who works night time or long shifts
• Have a sleep disorder
• Use medications that cause drowsiness

How Can I Prevent Impaired Driving?

It’s impossible to assess your level of impairment when you’re impaired.  To avoid any potential issues, commit to driving sober and making a plan to prevent driving while impaired/intoxicated. Driving while impaired or intoxicated to any degree is not only risky to your own personal health and well-being, but also increases the risk of danger to other drivers, passengers and pedestrians who you encounter while on the road. 

If you’re driving and notice the following symptoms, you should find a safe place to pull off the road and rest:

• Yawning
• Blinking frequently
• Drifting
• Hitting rumble strips

You can prevent drowsy driving by establishing good sleep habits and acknowledging when you’re too tired to drive. If you have a sleep disorder, seek medical advice for treatment options.

If you’ve been charged with a DUI or other impaired driving charge and need an ignition interlock device, Intoxalock can help. Our state specialists can help walk you through your state’s requirements.

We have 5,000+ installation centers nationwide. Contact us today to get started at 833-623-0200.