How can effects of both alcohol and drugs during a traffic stop be similarly assessed?

Evaluating a driver's ability to operate the vehicle safely is the most effective way to assess the effects of both alcohol and drugs during a traffic stop. Both substances can impair cognitive functions, motor skills, and judgment, which directly impact a driver's ability to control their vehicle. Law enforcement officers typically observe physical indicators such as coordination, balance, reaction time, and overall behavior during the stop to determine impairment.

This approach focuses on observable behaviors and skill performance rather than relying on subjective measures or assumptions about substances. By assessing how well a driver can perform tasks essential to safe driving, such as walking in a straight line or following instructions, officers can make informed judgments about potential impairment from either alcohol or drugs.

Other methods, such as identifying illegal substances or solely focusing on prescription medications, do not provide a complete picture of a driver’s impairment levels. Similarly, asking the driver their opinion on their driving skills can result in biased responses and does not offer objective evidence of impairment.