Field sobriety tests are road side evaluations made by law enforcement during a traffic stop when the officer suspects driving under the influence. Field sobriety tests are used as a basis for probable cause to arrest someone for DUI, in addition to other indications of impairment from your driving pattern and interaction with the officer.
 
Once you have been pulled over and have gotten out of your car, the officer will request you take some field sobriety tests. . The tests are used by law enforcement to help establish probable cause to arrest you for DUI bye valuating your level of intoxication. Keep in mind that field sobriety tests are NOT mandatory, regardless of what the officer may tell you.  There is no penalty for refusing to take the field sobriety tests.  In most cases, the officer will arrest you not even if you have taken the tests. .
 
Portable Breath Tests are used as a first check of your blood alcohol content. (BAC)  This test is usually not admissible in court and is only used to give the police officer insight to your level of intoxication and to help him establish probable cause for your arrest.  As with all roadside sobriety tests, a roadside breath test is not mandatory and it is recommended that you decline.
 
The National Highway Traffic and Safety Administration have identified three roadside sobriety tests as providing the most reliable results when trying to determine intoxication levels.  The NHTSA has provided guidelines for administering these tests to try and make them as accurate as possible.  The three tests that make up the “standardized field sobriety tests” are:

• ● The One Leg Stand
• ● Walk and Turn
• ● Horizontal Gaze Nystagmus Test

The One Leg Stand:
Police have specific protocols that must be followed when administering the One Leg Stand field sobriety test.   Before requesting you to conduct the test, the officer must consider specific details such as: are you more than 50 pounds overweight, over 65 years old or physically disabled? If any of those conditions apply to you, you should not take this test.  You should be allowed to remove your shoes prior to taking the test if you are wearing high heels more than 2″ high.
 
You also need to be allowed to take the test in a location safely away from traffic.  There is little chance of you passing this test if you are attempting it on a slippery area, a hillside or if it is windy.
 
If you are a good candidate to take this test and you agree to do so, the officer needs to describe and demonstrate the test before you begin.
 
When you begin, the first instruction from the officer will be to raise one of your legs six inches off the ground.  The decision of which leg to raise is yours.  The officer will tell you to keep your arms at your sides while raising your leg as you are not allowed to use them for balance.  When your leg is raised, the officer will then ask you to count out loud to 30 by thousands:  one thousand one, one thousand two etc. all the way up to 30.
 
For the duration of the test, the officer will observe you to check if you are using your arms to balance, if you put your foot down more than twice or if you sway while you are balancing.
 
One Leg Stand

• ● Instruction Stage – Stand with feet together and arms at side, don’t move out of this position until instructed to do so.
• ● Do you understand?
• ● Approximately 6 inches off the ground maintaining foot point
• ● Keep both legs straight, look at your raised foot, count aloud One thousand and one, one thousand and two, and so on until instructed to stop
• ● Police officer needs to time for 30 seconds
• ● Maximum of 4 clues for test

NHTSA certain people over 65 years of age, back, leg or inner ear conditions, or people who are overweight by 50 or more lbs. had difficulties conducting this test.
 
People wearing heels more than 2” high need to be provided with the opportunity to remove their shoes.
 
One Leg Stand “Clues” or “Cues”

1.   Sway
2.   Arms to balance
3.   Hops
4.   Puts foot down

Walk and Turn:
Another test that is used to determine if you are impaired or intoxicated is the Walk and Turn test.  Alcohol is widely known as a depressant that slows down your body’s central nervous system and thus makes impact your ability to perform this test.  The walk-and-turn test is standardized by the National Highway Traffic Safety Administration because they accept it generally is a dependable method for police officers to make the decision if a person is intoxicated.
 
Nonetheless, there are several things that can go wrong during the Walk and Turn test that will impact your performance and the officer’s view of your intoxication.
 
First of all, the police officer needs to be certain that you’re an appropriate candidate for this kind of test. Those who are over 65 years old, overweight in excess of 50 lbs. or anyone who has physical handicaps shouldn’t conduct this kind of test. If you’re able to take this physical test, the police officer really should first demonstrate it for you so you know what to try and do. They also need to make sure that you perform the test on a flat, dry area during practical weather conditions in a safe setting (away from traffic).
 
The tests consists of you being instructed to follow a line (either the white line on the shoulder of the road or an imaginary line if one is not available) by walking nine steps heel to toe.  Once you have counted the ninth and final step the officer will instruct you to rotate and return along the line in the same manner. . You are not allowed to use your arms to balance and if you sway, trip, miss steps or forget to count a loud, you will most likely fail this test.
 
Walk and Turn (Sometimes called the “Heel to Toe” test)

• ● Instruction stage – Left foot on line, right foot directly in front of left foot with heel touching toe
• ● Don’t move from this position until told to do so
• ● Do you understand?
• ● Walking Stage – When told to begin, take nine steps heel touching toe, when you reach your ninth step, leave your front foot on the line and turn making a number of small steps, and then come back nine steps heel to toe.  While you are doing this, keep your hands at your side, watch your feet at all times, count aloud and don’t stop until you have finished the test.
• ● Do you understand these instructions?
• ● Must miss heel to toe by ½” or more
• ● Must raise one or more hands 6” or more
• ● There can be no more than 8 clues.  Each clue might be observed many times, but still count only as one “clue”
• ● NHTSA “original research indicated that people over 65 years of age had difficulties performing this test.”  People with back, leg or inner ear conditions may have difficulty.
• ● 2” or greater heels need to be removed

Walk and Turn “Clues” or “Cues”

1. Can’t balance during instructions
2. Starts too soon
3. Stops
4. Misses heel to toe by ½” or more
5. Steps off line
6. Uses arms for balance
7. Turns incorrectly
8. Wrong number of steps

Horizontal Gaze Nystagmus Test:
Nystagmus is a medical condition when your eyes jerk involuntary.
 
Millions of people suffer from a natural nystagmus which explains why this test is not flawless.  Yes, drinking too much alcohol could contribute to someone’s nystagmus, but it does happen naturally.  Nystagmus also happens when you look side to side as far as you can.  This is more pronounced when the officer asks you to look to the corners of your eyes for a long time period.  After a short time of doing this, your eye muscles will become fatigued. . If the officer does not administer the test in the correct manner, the Horizontal Gaze Nystagmus test is useless when trying to determine your intoxication level. .
 
The reason law enforcement uses HGN as a field sobriety test is because alcohol can make nystagmus occur prior to your eyes reaching the very corners and could make nystagmus much more obvious. . Just like the other field sobriety tests, the HGN test must be given while paying attention to specific test procedures.  If the officer rushes the test, it could result in rapid eye movements, resulting in the officer incorrectly identifying nystagmus caused by intoxication.
 
What will happen during the HGN?
 
The officer will hold an object such as his pen, in front of your eyes approximately 12″ away from your nose.  He will then ask you to follow the pen with your eyes only, keeping your head still.  If you wear glasses, and cannot see the pen without them, you should be allowed to keep your glasses on. It is imperative that the officer ensures you will not be distracted by moving traffic or the lights on his car while you are taking the test.  Distractions such as these can negatively impact the results of your test.
 
Steps and Measurements
 
Horizontal Gaze Nystagmus

• ● Remove eyeglasses
• ● Check pupils for equal size. If the 2 pupils are noticeably different in size it’s possible the individual has a glass eye or some kind of neurological condition or head injury
• ● Check eyes to confirm they both track stimulus equally. When the eyes do not track with each other, the potential for serious medical condition or injury could be present.
• ● NHTSA “Testing for HGN in a person having an eye disorder or artificial eye hasn’t been validated by research.”
• ● Begin with Left Eye
• ● Check each eye separately
• ● Hold stimulus 12 to 15 inches in front of nose
• ● Check for a “lack of smooth pursuit” – Center to side in two (2) seconds
• ● Check both eyes 2 times to validate observations
• ● Look for “distinct nystagmus at maximum deviation” – Hold at Maximum Deviation for “minimum” four (4) seconds each time, nystagmus has to be Distinct and Sustained.
• ● Check both eyes 2 times to validate observations
• ● Check for “onset of nystagmus prior to 45 degrees” – The stimulus needs to be moved from 0 to 45 degrees at a rate taking four (4) seconds
• Check both eyes 2 times to validate observations

Vertical Gaze Nystagmus

• ● Position Stimulus 12 – 15 inches from nose
• ● Raise stimulus so that the person’s eyes are elevated as far as possible
• ● Hold for approximately four (4) seconds

Never expect the police officer to tell you this, but submitting to a field sobriety test is voluntary. Chemical testing such as blood or breath analysis is mandatory due to Ohio’s implied consent law.