Detection & Apprehension of Drivers


The detection and apprehension of drivers under the influence can be accomplished by either conducting sobriety checkpoints or by blanket patrols.

Sobriety checkpoints involve stopping vehicles based on a predetermined uniform plan such as every third car as they drive through a specific location.

More common are the blanket patrols where police officers attempt to locate these offenders by patrolling the roadways and observing the way they drive their vehicles.

The process of identifying and arresting drivers under the influence usually begins with observing the vehicle as it is being driven. The police officer typically looks for violations of the Vehicle and Traffic Law which may be as obvious as driving on the wrong side of a divided highway without headlights during hours of darkness or as subtle as delaying to pass a traffic signal light as it cycles from red to green.

The more violations the motorist commits, the greater the likelihood that they are driving under the influence.

Once the officer decides to pull over the vehicle, he activates his emergency lights and observes how the driver reacts. Reactions of those under the influence range from pulling over to striking objects alongside the roadway, jamming on the brakes, and continuing down the roadway oblivious to the police vehicle blaring behind them.

After the vehicle is stopped, the officer approaches and comes in face-to-face contact with the motorist. From this point on, the officer is constantly looking for clues in order to determine the sobriety of the driver.

The officer usually begins by asking for the drivers license, registration and insurance card. Simultaneously, the officer is attempting to detect odors of alcohol and drugs as well as masking odors like perfume that motorists may use to try to hide the latter two.

Additionally, the officer is evaluating the drivers eyes, speech, coordination and reactions to his requests.

The driver under the influence may inappropriately produce his social security card or fumble and drop his documents when asked for them.

Should the officer suspect the person is driving under the influence, he will instruct the motorist to exit the vehicle for the purpose of administering roadside standardized field sobriety tests (SFST).

These are divided attention tests that attempt to evaluate a motorists psychomotor condition and the ability to follow instructions by having them perform two or more relatively simple tasks at the same time in order to determine if they can do just that, divide their attention.

Being able to divide your attention is critical to driving a vehicle safely. Just think of how many things you must be aware of and do at the same time while driving.

The nine-step walk and turn, one-legged stand and the finger to nose are examples of the most common roadside tests.

The officer may also administer the horizontal gaze nystagmus test (HGN) which involves looking for the involuntary jerking of a persons eyeball when they follow a fixed stimulus such as a pen when they are under the influence of certain drugs including alcohol.

Upon the completion of these tests, if the officer is still not convinced as to the sobriety of the individual, he may administered a preliminary breath test (PBT) that will indicate if a person has a measurable amount of alcohol in their body.

The officer then makes a determination as to the sobriety of the individual based on the a totality of the circumstances and evidence, the manner in which they operated the vehicle and reacted to the intervention by the police officer to stop the vehicle.

Also, the officer makes a determination based upon the physical signs they exhibited upon initial contact, statements made, observed physical evidence, how they exit the vehicle and the results of the standardized field sobriety and or preliminary breath tests.

If the officer has probable cause to make an arrest for driving under the influence, he will place them under arrest and transport them usually to a central testing facility where a chemical test of their breath, blood or urine will be administered.

The results of these tests will determine the charges the person will face.

The driver charged with driving under the influence will usually be fingerprinted, photographed, physically searched and then lodged in a jail cell until they are transported to court for arraignment.

By: Lt. James Panarello.
Nassau County Police Department