Field Sobriety Tests Overview

The Heel-to-Toe test combines two tasks:

• Standing on a line (can be imaginary straight line) heel-to-toe.
• Maintaining balance while walking a line heel-to-toe.

The Heel-to-Toe test is an excellent test for divided attention impairment testing the subject’s ability to process information. Divided attention impairment involves a person’s ability to perform 2 or more acts — both mental and physical –at one time. It is widely accepted that balance and coordination are affected after the primary mental functions need for driving are affects. Consequently, when balance and coordination (physical acts) have been impaired by alcohol, a person’s ability to process information, divide attention, and assess performance (mental acts) has already been impaired also.

THIS TEST REQUIRES A DIVISION OF ATTENTION BETWEEN FIVE TASKS:

1. Maintaining a heel-to-toe position with arms at side while listening to instruction.
2. Maintaining balance while walking a straight line heel-to-toe
3. Keeping arms at sides.
4. Counting steps aloud.
5. Maintaining balance when turning to change direction.

TEST INSTRUCTIONS

• The suspect should put one foot on the line and the other foot behind it with the heel touching the toe.
• When the suspect assumes this position, the officer should continue with instructions. The subject should then be told to take a pre-instructed number of heel-to-toe steps down the line, turn around and take a pre-instructed number of heel-to-toe steps back.
• The suspect should keep his/her hands at their sides, watch their feet at all time, and count each step aloud. The officer should ensure the subject understands the direction prior to continuing. The subject should begin and count the first step form the heel-to-toe position as “one.”
• The suspect should make the turn by keeping one foot on the line and then use the other foot to step around.

SYMPTOMS OF INTOXICATION

• Loses balance during instructions by not maintaining heel-to-toe position throughout instructions.
• Starts before instructions are completely explained.
• Stops while walking or pauses for several seconds after a stop.
• Does not touch heel-to-toe or leaves a gap between heel and toe on any step.
• Subject steps to the side (off the line) in order to maintain balance
• Raises arms to balance.
• Loses balance while turning.
• Takes more or less than the pre-instructed number of steps in each direction,
• Cannot do the test. Steps off the line several times, is in danger of falling, or otherwise demonstrates inability to complete the test.

Also known as the “Standing on One Foot” test or tile “One-leg Stand” test.

TEST INSTRUCTIONS

• The suspect should be told to stand with his/her heels and toes together, arms down at their sides, raise one foot approximately six inches off the ground, and hold that position for approximately 30 seconds while counting from 1001 to 1030. A high-tolerance drinker at a BAC below 0.15 percent may be able to maintain his/her balance for 20-25 seconds but will likely falter after that time period; thusly, it is recommended that the suspect count aloud from 1001 to 1030 in order to estimate 30 seconds.
• The officer should demonstrate the test, ensure that the suspect understands the directions, and should not continue until the subject indicates understanding.

SYMPTOMS OF INTOXICATION

• Sways side-to-side or back-and-forth while balancing.
• Raises arms to balance.
• Able to keep one foot off the ground, but resorts to hopping to maintain balance.
• Puts foot down one or more times during 30-second count; not able to maintain one leg stand position.

• Suspect stands erect with feet together, eyes closed and arms outstretched in a downward position in front of them, at approximately 45 degrees from their body, keeping elbows straight. Alternating left hand and right hand, under the direction of the officer, the suspect bends forearm in from the elbow, attempting to touch the tip o fhis/her nose with the tip of his/her extended index finger.

SYMPTOMS OF INTOXICATION

• Sways.
• Opens eyes.
• Steps out of position.
• Fails to touch finger-to-nose.

TEST INSTRUCTIONS

• Suspect stands erect with heels and toes together, eyes closed, head tilted back, hands down at sides. The officer should allow 30 seconds or more to elapse before telling the subject to open his/her eyes. If eyes are opened before the 30 second time elapse the suspect should restart the time.

SYMPTOM OF INTOXICATION

• Sways.
• Opens eyes.
• Staggers out of position.
• Almost falls.

TEST INSTRUCTIONS

• First Alternative -> Suspect recites the alphabet. The officer should ascertain the suspect’s education level to ensure ability to perform the test.
• Second Alternative -> Suspect writes the alphabet on a piece of paper. To enhance evidentiary value, the suspect signs his/her name on the paper. The paper is then attached to the arrest report and retained with the original file.

SYMPTOMS OF INTOXICATION

• Is not able to correctly recite the alphabet.
• Is not able to correctly write the alphabet
• Forgets to date or sign the piece of paper.

TEST INSTRUCTIONS

• The officer should have the subject count using his/her fingers and thumb. The subject should touch tip of index finger to the tip of the thumb and count “one,” then middle finger to thumb and count “two,” and ring finger to thumb and count “three,” and the little finger to thumb and count “four.” The order is then reversed, four, three, two, and one.

SYMPTOMS OF INTOXICATION

• Is not able to coordinate the finger movements with speech
• Is not able to count correctly.

TEST INSTRUCTIONS

• The officer should have the suspect pat the back of one hand into the palm of the other hand and then turn top hand over and pat palm of top hand into palm of other hand. This test should be performed several times slowly at first then increasing to a relatively rapid pace.

SYMPTOMS OF INTOXICATION

• Is not able to coordinate hand movements as pace increases.
• Fails to increase pace of hand pat.

TEST INSTRUCTIONS

• PAS devices are handheld roadside devices about the size of a pocket calculator that require the suspect to blow into a balloon or a plastic tube about the size of a cigarette. PAS devices are calibrated to give either a pass/fail reading (set at either .05% BAC for no presumption but the collection of other corroborative evidence or .08% BAC for a presumption of intoxication) or a digital readout of the estimated BAC.
• Currently, California uses 2 models of Preliminary Breath Testing Devices that are on the National Highway Traffic Safety Administration (NHTSA) Conforming Products List (CPL) for evidential breath measurement devices.
  • I. The Alco-Sensor III
  • II. The Ako-Sensor IV

SYMPTOMS OF INTOXICATION

• PAS device gives a fail reading
• PAS device gives a digital readout of an estimated .08% or greater BAC