Police Identify Drunk Drivers through Signs of Impairment

​​Q:  What are police trained to look for when enforcing OVI (drunk driving) laws?
A:  An officer on OVI enforcement is trained to look for various signs of drunk driving, including:
1) signs of impairment exhibited by a person while driving a vehicle (called the “vehicle in motion” phase of enforcement);
2) signs of impairment upon the initial “personal contact” with the driver;
3) signs of impairment noticeable during the “pre-arrest screening” phase, which encompasses standardized field sobriety testing and preliminary breath testing.

Q:  What are “ signs of impairment” that an officer may notice while a person is driving?
A:  During the “vehicle in motion” phase, the officer looks for signs of impairment such as reckless driving, weaving, going left of center, driving too slowly, braking erratically, or stopping for no apparent reason, although almost any traffic violation may alert an officer to look for signs of impairment. In addition, an automobile accident that occurs during the late night or early morning hours will raise suspicion of impairment.

Q:  If I am stopped for a suspected drunk driving offense, what will an officer be looking for?
A:  Once you are pulled over, the officer will look for signs of impairment based on his or her observations, including  sight, hearing and smell. The officer may look for glassy or bloodshot eyes, soiled clothing, fumbling fingers, alcohol containers in your car, or any other unusual actions.  Slurred speech, admission to drinking, inability to answer a question while performing a physical task (such as retrieving your license and insurance information), inconsistent responses and unusual statements will also alert an officer. The odor of alcoholic beverages, cover-up odors, or any other unusual odors may raise the officer’s suspicion. 

Q:  Am I under arrest if the officer asks me to exit my car?
A:  No. When you exit the vehicle, the officer will be watching for difficulty in opening the car door, using the door for balance, leaning against the vehicle and swaying or staggering.

Once you are out of the car, the officer may ask you to take field sobriety tests. If you opt to take the tests, your performance on the tests can be used in the officer’s determination to arrest you.

The officer may offer you a preliminary breath test (PBT). A PBT is a breath test performed with an instrument that approximates your blood alcohol content (BAC). While you are not required to submit to this test and a PBT result generally is not admissible at trial, your refusal to submit to a PBT may be used as evidence of your guilt.


This "Law You Can Use" consumer legal information column was provided by the Ohio State Bar Association. It was originally prepared by attorney Jon J. Saia, a partner in the Columbus law firm, Saia & Piatt, Inc., and updated by associate Jessica G. D'Varga of the same firm.

Articles appearing in this column are intended to provide broad, general information about the law. This article is not intended to be legal advice. Before applying this information to a specific legal problem, readers are urged to seek advice from a licensed attorney.



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