A Resource for Law Enforcement Personnel
The National Highway Traffic Safety Administration has developed a set of fourteen behavioral cues that can be used by law enforcement personnel to accurately detect motorcyclists who are operating their vehicles while intoxicated.
The cues have been labeled as "excellent predictors" and "good predictors" based on study results. The excellent cues predicted impaired motorcycle operation 50 percent or more of the time. The good cues predicted impaired motorcycle operation 30-49 percent of the time.
Primary Indicators (50+ percent probability)
Drifting during a turn or in a curve
Trouble with dismount
Trouble with balance at a stop
Turning problems (unsteady, sudden corrections, late braking, improper lean angle)
Inattentive to surroundings
Inappropriate or unusual behavior
Weaving (note that riders will swerve to avoid hazards and often utilize various positions within a traffic lane to be seen by other drivers or to avoid hazards)
Secondary Indicators (30-49 percent probability)
Erratic movements while going straight
Operating without lights at night
Recklessness
Following too closely
Running a stop light or stop sign
Evasion
Travelling the wrong way in a lane