An officer is trained to take notes during the evidence gathering stage. However sometimes an officer will make a mental summary of the evidence collected during 1) vehicle in motion stage, 2) personal contact stage, and 3) pre arrest screening. The amount of information an officer has to record is overwhelming.
An officer is specially trained to look for people who drive under the influence. When police officer gather evidence to determine if a person should be arrested for a DUI violation they ask themselves three questions. Should I stop the car? Should the driver exit? Is there probable cause to arrest the suspect for DUI? Today, we will cover the first of three stages.
First an officer will ask himself “should I stop the car?” This is also known as phase 1: vehicle in motion. This involves the initial observation of vehicle and operation. This means they are looking for certain symptoms of impairment to manifest itself in your driving.
These things can include failure to maintain proper lane position which manifests itself in weaving, weaving across lanes, straddling a lane, swerving, turning with wide radius, drifting, and almost striking an object or another vehicle. The officer is also trained to look for speed and braking problems. These problems can manifest itself in stopping too far, or jerky stop. The office officer is also trained to look for rapid acceleration or deceleration, whether a person is alternating between speeding up, slowing down and also if they are going too slow. (10 miles under the limit.)
Vigilance problems in driving are also an issue. These problems manifest itself in driving in the opposite lane, going down the wrong way street, a slow response to traffic signals, a slow or failure to respond to an officer signals, stopping in the lane for no apparent reason, driving without headlights at night, and failure to signal or signal inconsistent with action.
Judgment problems are also an issue. These can manifest itself in a driver following another car too closely, improper or unsafe lane change, illegal or improper turning (meaning turning too fast). An officer is also trained to look for improper response when he signals for you. When an officer signals for you to pull over stopping inappropriately will also count against you. For example, stopping in a prohibited zone, or at a crosswalk. Drinking in the vehicle, urinating at roadside, arguing without cause and other disorderly actions are also visual cues that the officer is trained to look for.
An officer is also trained to look for people who appear impaired when driving. This could include eye fixation on the road, tightly gripping the steering wheel, slouching in the seat, gesturing erratically or the infamous face close to the windshield.
A lot of these cues can occur when a person is tired or distracted. For example when a person uses a cell phone and gets distracted, this will result in weaving or drifting or striking another vehicle. Also when a person realizes there is a police officer behind them, they may keep their eye on the rearview mirror, which results in drifting and weaving because the eyes are off the road. It is perfectly natural to feel uncomfortable when a police officer is behind you. This is also known as black-and-white fever.
Some people are cautious drivers and drive below the speed limits quite often, or some of us make snap decisions and go for U-turn at the last minute; this does not mean a person is impaired. These cues are part of a calculus the police officer would use in deciding whether or not to stop you.
