Comparing Drugged and Alcohol-Impaired Driving

Person holding cannabis leaf

Operating a vehicle under the influence of alcohol or drugs significantly endangers public safety. Although drunk driving has been the focus of public awareness campaigns for years, drugged driving has received comparatively less attention.

Statistics Canada data reveals that in 2019, there were 6,453 reported drug-impaired driving cases, accounting for 8% of all impaired driving incidents and reflecting a 43% increase from 2018. Alcohol-impaired driving, similarly impacted by new legislation, saw a 15% increase in 2019.

Differentiating Alcohol and Drug-Impaired Driving

The legal limit for alcohol is based on the amount that could impair an individual’s ability to drive safely. This limit serves as the foundation for Impaired Driving Charges and underscores the key distinction between alcohol and drug-impaired driving currently.

For both illegal and legal drugs, there is no agreed-upon limit or threshold indicating impaired driving skills. This is due to the lack of a well-established dose-response relationship for various impairing drugs. As a result, drugged driving charges can be harder to prove or dispute.

Drug impairment effects can vary over time, and the impact of different drug concentrations depends on several factors, such as:

  • Age
  • Sex
  • Frequency of use
  • Metabolism and body fat
  • Presence of other impairing substances

Furthermore, the effects of some drugs may diminish over time, while higher levels of others might not necessarily lead to increased impairment. This complexity makes it difficult to establish a universal limit for drug-impaired driving.

Detection and Testing

Alcohol impairment detection is relatively simple, employing standardized methods like breathalyzer tests and field sobriety tests. However, drug impairment detection can be more complicated, depending on the drug present in the driver’s system. No universally accepted standard test measures drug impairment, and drug detection times vary based on the substance, dosage, and individual metabolism.

Oral fluid drug screeners are quick, non-invasive, and accurate tools that police can use to detect the presence of certain drugs, including THC and cocaine, in a driver’s oral fluid. If an officer reasonably suspects a driver has drugs in their system based on objective facts, such as red eyes, muscle tremors, agitation, or abnormal speech patterns, they can demand an oral fluid sample.

A positive test result, along with other observed signs of impairment or drug use, may provide grounds for further investigation, including a blood sample demand. Police may also require a driver to submit to a Standard Field Sobriety Test (SFST) or a Drug Recognition Expert Evaluation (DRE) during their investigation.

Prohibited Levels

Separate offenses exist for having specific prohibited levels of alcohol, cannabis, or certain other drugs in the blood within two hours of driving, in addition to impaired driving.

Alcohol: 80 milligrams (mg) or more of alcohol per 100 milliliters (ml) of blood.

Cannabis (THC): Two prohibited levels exist for THC, the primary psychoactive component of cannabis: it is a less severe offense to have between 2 nanograms (ng) and 5 ng of THC per ml of blood. It is a more severe offense to have 5 ng of THC or more per ml of blood.

Combination of alcohol and cannabis: When found in combination, the prohibited levels of alcohol and cannabis are 50mg or more of alcohol per 100ml blood and 2.5 ng or more of THC per ml of blood.

Other drugs: Having any detectable amount of LSD, psilocybin, psilocin (“magic mushrooms”), ketamine, PCP, cocaine, methamphetamine, or 6-mam (a heroin metabolite) in your system within two hours of driving is also prohibited.

The prohibited level for GHB is 5mg or more per liter of blood, as the body can naturally produce low levels of this drug.

Source: Government of Canada: Impaired Driving Laws

Legal Consequences

Both drunk and drugged driving are illegal and carry severe penalties, including fines, license suspension, and potential imprisonment.

The penalties for drunk driving and drugged driving are nearly identical:

1st offence: Mandatory minimum fine of $1000; Maximum imprisonment of 10 years

2nd offence: Mandatory minimum 30 days imprisonment; Maximum imprisonment of 10 years

3rd offence: Mandatory minimum 120 days imprisonment; Maximum imprisonment of 10 years

How Cannabis Affects Driving Skills

The effects of marijuana on individuals can vary greatly. Numerous factors contribute to these differences, including:

  • The method of consumption
  • The quantity consumed
  • The specific marijuana strain
  • THC concentrations

Due to the varied effects of these factors, there is no clear guideline on the “safe” amount of marijuana consumption prior to driving. Moreover, it is unclear how long one should wait after using marijuana before it is considered safe to drive.

How Marijuana Impairs Driving Capabilities

Marijuana impairs driving abilities by affecting the following skills:

  • Motor coordination
  • Reaction time
  • Short-term memory and concentration
  • Maintaining a steady path
  • Keeping consistent and safe speeds
  • Decision-making abilities
  • Handling unexpected situations

Consequently, it is advised to refrain from driving if you have recently used marijuana.

Driving Under the Influence of Other Substances

Laws and regulations concerning impaired driving typically focus on a driver’s capacity to safely operate a vehicle rather than the specific substance causing the impairment. Besides cannabis, prescription drugs (such as opioids, cold medications, and pain relievers), over-the-counter medications, and illicit drugs (like cocaine and LSD) can also impair driving abilities.

Although over-the-counter and prescription drugs are legal when prescribed by a healthcare professional, driving under their influence is still considered impaired driving if they affect the driver’s ability to safely operate a vehicle. It is crucial for drivers to read the labels and adhere to the recommended dosages for these medications to minimize impairment risks.

How Alcohol Affects Driving Abilities

Alcohol impairs driving by affecting various cognitive and motor skills essential for safely operating a vehicle. When a person consumes alcohol, it is absorbed into the bloodstream and impacts the central nervous system. The degree of impairment depends on factors such as the volume of alcohol consumed, the consumption rate, body weight, and individual tolerance. Some key ways alcohol impairs driving include:

  • Slower reaction time
  • Hindered motor coordination
  • Difficulty focusing
  • Blurred or double vision
  • Sleepiness and fatigue
  • Overconfidence

Since even small amounts of cannabis can affect reaction time, driving with any trace of it in your system can increase the likelihood of accidents. Regardless of whether you have consumed alcohol, used drugs, or taken legal medications, driving while impaired is never advisable.

If you have been charged with drugged or drunk driving, call or text us 24 hours a day, seven days a week at 1 (855) 585-1777.

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