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DUI SERVICE PROVIDER ORIENTATION
DAY 1 Afternoon Session
THE DUI ARREST PROCESS
STANDARDIZED FIELD SOBRIETY TESTING
AND BAC DETERMINATION
9/4/2019
1
The LegalEnvironment
DWI Detection and Standardized Field Sobriety Testing
Basic DWI Statute
III-1
It is unlawful for any person to...
• operate or be in actual physical control of …
• any vehicle ...
• within this state ...
• while under the influence of alcohol and/or any drug.
DWI Detection and Standardized Field Sobriety Testing
Key Features of Implied Consent
• Any person who operates a motor vehicle upon the public highways of this state …
• Shall be deemed to have given consent to a chemical test …
• For the purpose of determining the alcohol and/or drug content of that person’s blood …
• When arrested for any acts alleged to have been committed while the person was operating or in actual physical control of a vehicle while under the influence of alcohol and/or any drug.
III-2
The Legal Environment
9/4/2019
2
DWI Detection and Standardized Field Sobriety Testing
Legal Presumptions
or more…Presumed under the influence
Less than …
Presumed not under the influence
At least but below
No presumptionIII-3
DWI Detection and Standardized Field Sobriety Testing
Key Point:
Chemical test evidence is PRESUMPTIVE,Not Conclusive
III-4
DWI Detection and Standardized Field Sobriety Testing
Question Number 1
Is it possible for a person whose BAC is above the state’s per se or presumptive level to be
acquitted of DWI?III-5
9/4/2019
3
DWI Detection and Standardized Field Sobriety Testing
Question Number 2
Is it possible for a person whose BAC was below the state’s per se or presumptive level to be
convicted of DWI?
III-6
DWI Detection and Standardized Field Sobriety Testing
Illegal “Per Se” Statute
Is it unlawful for any person to…
• operate or be in actual physical control of…
• any vehicle…
• within this state…
• while having a BAC at or above state’s level.
III-7
DWI Detection and Standardized Field Sobriety Testing
9/4/2019
4
Phase One:Vehicle In Motion
DWI Detection and Standardized Field Sobriety Testing
V-1
Initial Observationof the Vehiclein Operation
Observation ofthe Stop
Should I Stopthe Vehicle? ?
Phase One: Vehicle in Motion
DWI Detection and Standardized Field Sobriety Testing
V-2
Common Symptoms ofAlcohol Influence
Blood Alcohol Concentration
ImpairedVision
0.08
PoorCoordination
0.10
SlowedReaction
0.03
IncreasedRisk
Taking
0.05
Phase One: Vehicle In Motion
---c __ ~ ---
fJ ••••
9/4/2019
5
DWI Detection and Standardized Field Sobriety Testing
V-3
Most Common and ReliableInitial Indicators of DWI
• Turning with wide radius.• Almost striking object or vehicle.• Weaving.• Straddling center or lane marker.• Appearing to be impaired.• Driving on other than designated roadway.• Driving into opposing or crossing traffic.• Slow response to traffic signals.• Turning abruptly or illegally.• Stopping inappropriately.
• Accelerating/decelerating rapidly.• Headlights off.• Swerving.• Following too closely.• Drifting.• Speed slower than 10mph below limit.• Stopping without cause in traffic lane.• Tires on center or lane marker.• Braking erratically.• Signaling inconsistent with driving.
DWI Detection and Standardized Field Sobriety Testing
V-4
Motorcycle DUI Detection Guide
Excellent Cues (50% or Greater Probability)• Drifting during turn or curve
• Trouble with dismount
• Trouble with balance at a stop
• Turning problems (e.g., unsteady, sudden corrective, late breaking, improper lean angle)
• Inattentive to surroundings
• Inappropriate or unusual behavior (e.g., carrying or dropping object, urinating at
roadside, disorderly conduct, etc.)
• Weaving
Good Cues (30 to 50% Probability)• Erratic movements while going straight
• Operating without lights at night
• Recklessness
• Following too closely
• Running stop light or sign
• Evasion
• Travelling wrong way
DWI Detection and Standardized Field Sobriety Testing
V-5
Safe driving demands the abilityto divide attention among
numerous simultaneous tasks
9/4/2019
6
DWI Detection and Standardized Field Sobriety Testing
V-6
Vehicle in Motion
What Do You See?
Moving Violation?
Equipment Violation?
Other Violation?
Unusual Operation?
Anything Else?
DWI Detection and Standardized Field Sobriety Testing
V-7
Phase One: Task OneInitial Observation of Vehicle Operation
Requires the Ability to:
1. Recognize evidence of alcohol and/or other drug influence
2. Describe that evidence clearly and convincingly
DWI Detection and Standardized Field Sobriety Testing
V-8
Vehicle in Motion
Tries to Flee?No Response?
Slow Response?Abrupt Weave?
What Do You See?
Sudden Stop?Strikes Curb?
New Violations?Anything Else?•
I _J
9/4/2019
7
DWI Detection and Standardized Field Sobriety Testing
Phase One: Task TwoObservation of the Stop
Requires the Ability to:
1. Recognize evidence of alcohol and/or other drug influence
2. Describe that evidence clearly and convincingly
V-9
DWI Detection and Standardized Field Sobriety Testing
Phase Two:Personal Contact
Phase Two: Perc:nn:::11 Contact
9/4/2019
8
DWI Detection and Standardized Field Sobriety Testing
VI-1
Interview andObservationof the Driver
Observation ofthe Exit
Should DriverExit? ?
Phase Two: Personal Contact
DWI Detection and Standardized Field Sobriety Testing
VI-2
Personal Contact
Bloodshot Eyes?Soiled Clothing?
Fumbling Fingers?Alcohol Containers?
Drug and drug paraphernalia?Bruises, Bumps, Scratches?
Unusual Actions?
What Do You See?
DWI Detection and Standardized Field Sobriety Testing
Personal Contact
What Do You Hear?
VI-3
Slurred Speech?Admission of Drinking?
Inconsistent Responses?Unusual Statements?Abusive Language?
Anything Else?
9/4/2019
9
DWI Detection and Standardized Field Sobriety Testing
Personal Contact
What Do You Smell?
VI-4
Alcoholic Beverage?“Cover-Up” Odors?
Marijuana?Other Unusual Odors?
DWI Detection and Standardized Field Sobriety Testing
VI-5
Phase Two: Task One
Face-to-Face Observation andInterview of Suspect
Requires the Ability to:
1. Recognize the sensory evidence of alcohol and/or other drug influence
2. Describe the evidence clearly and convincingly
DWI Detection and Standardized Field Sobriety Testing
Interview/Questioning Techniques
VI-6
• Simultaneously request license and registration
• Pose distracting/interrupting questions during license search
• Pose unusual questions to verify license information
9/4/2019
10
DWI Detection and Standardized Field Sobriety Testing
The Exit
What Do You See?
VI-7
Angry, Unusual Reaction?Can’t Follow Directions?
Can’t Open Door?Leaves Car in Gear?
“Climbs” Out of Car?Leans Against Car?
Keeps Hand on Car?Anything Else?
DWI Detection and Standardized Field Sobriety Testing
Phase Three:Pre-Arrest Screening
Phase Three: Pre-Arrest Screening
9/4/2019
11
DWI Detection and Standardized Field Sobriety Testing
VII-1
Should I Arrest?
?
Phase Three: Pre-Arrest Screening
Field SobrietyTesting
PreliminaryBreath Testing
DWI Detection and Standardized Field Sobriety Testing
VII-2
Psychophysical Tests
Methods of examiningmental and/or physical impairment
DWI Detection and Standardized Field Sobriety Testing
Nystagmus:Involuntary Jerking of the Eyes
VII-3
9/4/2019
12
DWI Detection and Standardized Field Sobriety Testing
VII-4
“Divided Attention”
…Concentrating on more than one thing ata time (mental tasks and physical tasks)
DWI Detection and Standardized Field Sobriety Testing
VII-5
Typical Simultaneous CapabilitiesRequired for Driving
• Information Processing• Short-term Memory• Judgment/Decision Making• Balance• Quick Reactions• Clear Vision• Small-Muscle Control• Coordination of Limbs
DWI Detection and Standardized Field Sobriety Testing
VII-6
The SuspectThe Jurors
Anyone Like The Suspect
You The Judge
SimplicityIs it Reasonable to Assume That, If Sober...
…Would “Pass” the Test?
9/4/2019
13
DWI Detection and Standardized Field Sobriety Testing
Walk and Turn(Divided Attention Test)
VII-7
• Instructions Stage
• Walking Stage
DWI Detection and Standardized Field Sobriety Testing
One Leg Stand(Divided Attention Test)
VII-8
• Instructions Stage
• Balance and Counting Stage
DWI Detection and Standardized Field Sobriety Testing
Basic Purpose of PreliminaryBreath Testing
VII-9
Demonstrate Association of Alcoholwith the Observable Evidence of
the Suspect’s Impairment
9/4/2019
14
DWI Detection and Standardized Field Sobriety Testing
Advantages of PBT
VII-10
• Corroborate other evidence
• Confirm officer’s judgment
• Confirm alcohol as cause of impairment
• Help establish probable cause for DWI arrest
DWI Detection and Standardized Field Sobriety Testing
Possible Factors AffectingPreliminary Breath Tests
• Breath sample composition
• Breath sample cooling
• Residual mouth alcohol
• Contaminants in the breath
• Radio frequency interference
VII-11
DWI Detection and Standardized Field Sobriety Testing
The Arrest Decision is Based on All EvidenceAccumulated During All Three Detection Phases
VII-12
Initial Observation ofVehicle Operation
Face-to-FaceObservation
andInterview
PsychophysicalTests
PreliminaryBreath Tests
Observationof the
Exit
Observation ofthe Stop
9/4/2019
15
Concepts and Principles of theStandardized Field Sobriety
Tests (SFST)
DWI Detection and Standardized Field Sobriety Testing
Overview:Development and Validation
NHTSA Research Began in 1975 in CaliforniaWith Three Final Reports Being Published:
1. California: 1977 (lab study only)
2. California: 1981 (lab/field study)
3. Maryland, Washington, DC, Virginia, North
Carolina: 1983 (field study only)
VIII-1
Concepts and Principles of the Standardized Field Sobriety
Tests {SFST)
9/4/2019
16
DWI Detection and Standardized Field Sobriety Testing
Original Research Objectives
VIII-1A
• To evaluate currently used physical coordination tests to determine their relationship to intoxication and driving impairment.
• To develop more sensitive tests that would provide more reliable evidence of impairment.
• To standardize the tests and observations.
DWI Detection and Standardized Field Sobriety Testing
Volunteers were Subjected toSix Tests:
VIII-2
1. One-leg stand
2. Finger to nose
3. Finger count
4. Walk and turn
5. Tracing (a paper and pencil exercise)
6. Nystagmus (called alcohol gaze nystagmus in
final report)
DWI Detection and Standardized Field Sobriety Testing
Laboratory Test Data
VIII-3
• HGN by itself was 77% accurate.
• Walk and Turn was 68% accurate.
• One Leg Stand was 65% accurate.
• It would be possible to combine the results of
HGN and Walk and Turn and be 80% accurate.
Results
9/4/2019
17
DWI Detection and Standardized Field Sobriety Testing
“Standardized” Elements
VIII-4A
• Standardized Administrative Procedures
• Standardized Clues
• Standardized Criteria
DWI Detection and Standardized Field Sobriety Testing
Importance of Large Scale FieldValidation Study
VIII-4B
• First significant assessment of the
workability of the standardized tests under
actual enforcement conditions.
• First time completely objective clues and
scoring criteria had been defined for the
tests.
• Results of the study validated the SFSTs.
DWI Detection and Standardized Field Sobriety Testing
SFSTField Validation Studies
VIII-5
Colorado1995
Florida1997
San Diego, California1998
9/4/2019
18
DWI Detection and Standardized Field Sobriety Testing
Colorado Field Validation Studyof
SFST
VIII-6
• First full field validation study using SFST
experienced law enforcement personnel.
• 93% correct arrest decision based on
three-test battery (HGN, WAT, OLS).
DWI Detection and Standardized Field Sobriety Testing
Florida Field Validation Studyof
SFST
VIII-7
• 95% correct arrest decision based on
three-test battery (HGN, WAT, OLS).
• Validated SFST’s at 0.08 BAC and above.
DWI Detection and Standardized Field Sobriety Testing
San Diego Field Validation Studyof
SFST
VIII-8
• 91% correct arrest decision for 0.08 BAC
and above using three-test battery (HGN,
WAT, OLS).
• HGN is still most reliable of three-test
battery and supports arrest decisions at
0.08 BAC.
9/4/2019
19
DWI Detection and Standardized Field Sobriety Testing
Horizontal Gaze Nystagmus
VIII-9
Involuntary jerking of the eyes occurring asthe eyes gaze to the side.
DWI Detection and Standardized Field Sobriety Testing
Categories of Nystagmus
VIII-10
• Vestibular- Rotational- Post-rotational- Caloric- Positional alcohol nystagmus
• Neural- Optokinetic- Physiological- Gaze
HorizontalVerticalResting
• Pathological disorders and diseases
DWI Detection and Standardized Field Sobriety Testing
Administrative Procedures
VIII-11
1. Eyeglasses
2. Verbal instructions
3. Position object (12-15 inches) (30-38 cm)
4. Pupil size and resting nystagmus
5. Equal tracking
9/4/2019
20
DWI Detection and Standardized Field Sobriety Testing
Administrative Procedures
VIII-11A
6. Check for lack of smooth pursuit
7. Check for distinct and sustained nystagmus at maximum
deviation
8. Check for onset of nystagmus prior to 45 degrees
9. Total the clues
10. Check for Vertical Gaze Nystagmus
Check each eye independently beginning with the suspect’s left and compare.
DWI Detection and Standardized Field Sobriety Testing
Three Clues ofHorizontal Gaze Nystagmus
VIII-12
• Lack of smooth pursuit.
• Distinct and sustained nystagmus at maximum deviation.
• Onset of nystagmus prior to 45 degrees.
DWI Detection and Standardized Field Sobriety Testing
Clue Number 1
VIII-13
Lack of smooth pursuit
9/4/2019
21
DWI Detection and Standardized Field Sobriety Testing
Clue Number 2
VIII-14
Distinct and sustained nystagmus at maximum deviation
DWI Detection and Standardized Field Sobriety Testing
Clue Number 3
VIII-15
Onset of nystagmus prior to 45 degrees
45o
DWI Detection and Standardized Field Sobriety Testing
45o
VIII-16
9/4/2019
22
DWI Detection and Standardized Field Sobriety Testing
Horizontal GazeNystagmus Test Criterion
VIII-17
4 or more clues indicates BAC above 0.10(77% accurate)
4
DWI Detection and Standardized Field Sobriety Testing
Vertical Gaze Nystagmus
VIII-18
DWI Detection and Standardized Field Sobriety Testing
Walk and Turn(Divided Attention Test -
Mental Task and Physical Task)
• Instructions Stage
• Walking Stage
VIII-19
9/4/2019
23
DWI Detection and Standardized Field Sobriety Testing
Administrative Procedures
VIII-20
1. Verbal Instructions:- Assume heel-toe stance- Arms down at sides- Don’t start until told
2. 9 heel-to-toe Steps, Turn, 9 heel-to-toe Steps
3. Turn Procedures:- Turn around on line- Several small steps
4. While Walking:- Keep watching feet- Arms down at sides- Count steps out loud- Don’t stop during walk
DWI Detection and Standardized Field Sobriety Testing
Walk and Turn Test Clues
VIII-21
1. Can’t balance during instructions
2. Starts too soon
3. Stops while walking
4. Doesn’t touch heel-to-toe
DWI Detection and Standardized Field Sobriety Testing
Walk and Turn Test Clues
VIII-21A
5. Steps off line
6. Uses arms to balance
7. Improper turn (or loses balance on turn)
8. Wrong number of steps
Note: If suspect can't do the test, record observed clues and document the reason for not completing the test.
9/4/2019
24
DWI Detection and Standardized Field Sobriety Testing
Walk and Turn TestCriterion
VIII-22
2 or more clues indicates BAC above 0.10(68% accurate)
2
DWI Detection and Standardized Field Sobriety Testing
One-Leg Stand
(Divided Attention Test -Mental Task and Physical Task)
VIII-23
• Instructions Stage
• Balance and Counting Stage
DWI Detection and Standardized Field Sobriety Testing
Administrative Procedures
VIII-24
Instructions Stage:- Stand straight, feet together- Keep arms at sides- Maintain position until told otherwise
9/4/2019
25
DWI Detection and Standardized Field Sobriety Testing
Administrative Procedures
VIII-24A
Note: It’s important for the officer to time the 30 second count for the test.
Balance and Counting Stage:- Raise one leg, either leg
- Keep raised foot approximately six inches (15 cm) off
ground, foot parallel to the ground
- Keep both legs straight
- Keep eyes on elevated foot
- Count out loud in the following manner: “One thousand
and one, one thousand and two, one thousand and three and
so on”, until told to stop
DWI Detection and Standardized Field Sobriety Testing
One-Leg Stand Test Clues
VIII-25
• Sways while balancing
• Uses arms to balance
• Hops
• Puts foot down
Note: If suspect can't do the test, record observed clues and document the reason for not completing the test.
DWI Detection and Standardized Field Sobriety Testing
One-Leg Stand TestCriterion
VIII-26
2 or more clues indicates BAC above 0.10(65% accurate)
2
9/4/2019
26
DWI Detection and Standardized Field Sobriety Testing
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6/20
05
1
DUI ARREST FLOW CHART
.A • ~ Police arrests offender for DUI and issues a Law Enforcement Sworn Report /Statutory
Summary Suspension (SSS)
Offender goes to Court for DUI; also has right to contest the summary suspension in a separate hearing.
If found guilty of DUI, judge orders offender to get an evaluation
DASA provider completes evaluation
Offender returns to judge for sentencing.
✓ If convicted, then driving privileges are revoked. If sentenced to court supervision, then offender can resume
driving after termination of summary suspension.
✓ If offender contests summary suspension at an Implied Consent hearing, then judge can rescind the Statutory
Summary Suspension, but if not, the client will lose driving privileges 46 days after arrest.
✓ If offender is a first offender, they can accept a monitoring device driving permit from the Secretary of State
BAIID Division.
✓ If offender is not a first offender, then offender cannot drive during the summary suspension.
✓ If the judge rescinds the Statutory Summary Suspension, then the summary suspension is removed from driving
record and offender is free to resume driving, unless convicted/revoked for the DUI, in which case the offender
will have to go to the Secretary of State for driving relief.
✓ Offender follows judge's orders for treatment, risk education, etc.
Development or a
Standardized Field Sobriety Test
f~-=~•.· - -----&IN
APPENDIX A Standardized Field Sobriety Testing
The Standardiz.ed Field Sobriety Test (SFS1) is a battery of three tests administered and evaluated in a standardiz.ed manner to obtain validated indicators of impainnent and establish probable cause for arrest. These tests were developed as a resuh of research sponsored by the National Highway Traffic Safety Administration (NHTSA) and conducted by the Southern California Research Institute. A formal program of training was developed and is available through NHTSA to help law enforcement officers become more skillful at detecting DWI suspects, describing the behavior of these suspects, and presenting effective testimony in court. Formal administration and accreditation of the program is provided through the International Association of Chiefs of Police (IACP). The three tests of the SFST are:
• Horizontal Gaz.e Nystagmus (HGN), • Walk-and-Tum(WA1), • and One-Leg Stand (OLS).
These tests are administered systematically and are evaluated according to measured responses of the suspect.
HGN Testing
Horizontal Gaz.e Nystagmus is an involuntary jerking of the eye that occurs naturally as the eyes gaz.e to the side. Under normal circUill'itances, nystagmus occurs when the eyes are rotated at high peripheral angles. However, when a person is impaired by alcohoL nystagmus is exaggerated and may occur at lesser angles. An alcoholimpaired person will also often have difficuhy smoothly tracking a moving object. In the HGN test, the officer observes the eyes of a suspect as the suspect follows a slowly moving object such as a pen or small flashlight, horizontally with his or her eyes. The examiner looks for three indicators of impainnent in each eye: if the eye cannot follow a moving object smoothly, if jerking is distinct when the eye is at maximum deviation, and if the angle of onset of jerking is within 45 degrees of center. I~ between the two eyes, four or more clues appear, the suspect likely has a BAC of 0.08 or greater. NHTSA research found that this test allows proper classification of approximately 88 percent of suspects (Stuster and Burns, 1998). HGN may also indicate consumption of seizure medications, phencyclidine, a variety of inhalants, barbiturates, and other depressants.
Walk and Turn
The Walk-and-Tum test and One-Leg Stand test are "divided attention" tests that are easily performed by most
unimpaired people. They require a suspect to listen to and follow instructions while performing simple physical
movements. Impaired persons have difficulty with tasks requiring their attention to be divided between simple
mental and physical exercises.
In the Walk-and-Tum test, the subject is directed to take nine steps, heel-to-toe, along a straight line. After
taking the steps, the suspect must turn on one foot and return in the same manner in the opposite direction. The
examiner looks for eight indicators of impairment: if the suspect cannot keep balance while listening to the
instructions, begins before the instructions are finished, stops while walking to regain balance, does not touch
heel-to-toe, steps off the line, uses arms to balance, makes an improper turn, or takes an incorrect number of steps. NHTSA research indicates that 79 percent of individuals who exhibit two or more indicators in the
performance of the test will have a BAC of 0.08 or greater (Stuster and Burns, 1998).
One Leg Stand
In the One-Leg Stand test, the suspect is instructed to stand with one foot approximately six inches off the
ground and count aloud by thousands (One thousand-one, one thousand-two, etc.) until told to put the foot
down. The officer times the subject for 30 seconds. The officer looks for four indicators of impairment, including
swaying while balancing, using arms to balance, hopping to maintain balance, and putting the foot down. NHTSA research indicates that 83 percent of individuals who exhibit two or more such indicators in the performance of
the test will have a BAC of 0.08 of greater (Stuster and Burns, 1998).
Combined Measures
When the component tests of the SFST battery are combined, officers are accurate in 91 percent of cases,
overall, and in 94 percent of cases if explanations for some of the false positives are accepted (Stuster and
Burns, 1998).
The original NHTSA research found different accuracies for the SFST Battery than reported in the more recent
study. Tharp, Burns, and Moskowitz (1981) reported accuracies of 77 percent for the HGN, 68 percent for the
Walk and Turn, and 65 percent for the One Leg Stand components; 81 percent of officers' arrest decisions at
0.10 BAC were correct when all three measures were combined. In contrast, Stuster and Burns (1998) found
greater accuracies in making arrest decisions on the basis of SFST results in their study at 0.08 percent BAC, as
descnbed previously and sunnnarized in the following table.
Comparison of SFST Accuracies 1981 vs. 1998
Study: Combined Tharp, Burns, & Moskowitz (1981)
• BAC: 0.10
• HGN: 77%
• WAT:8%
• OLS: 65%
• Combined: 81 %
Study: Stuster & Bums (1998)
• BAC: 0.08
• HGN: 88%
• WAT: 79%
• OLS: 83%
• Combined: 91%
The greater component and overall accuracies found during the 1998 study are attnbutable to 17 years of law enforcement experience with the SFSTs since the original study and a lower criterion BAC than in the original
study (ie., 0.08 vs. 0.10 percent).
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