Policy Text
CATEGORY DATE ADOPTED LAST REVIEW
1 01/24/2011 11/01/201 9
TUSTIN POLICE DEPARTMENT
STANDARD OPERATING PROCEDURES
CP506 - DUI Procedure 1 CP506 DUI INVESTIGATION PROCEDURE S
CP506 .1 PURPOSE AND SCOPE
The purpose of this procedure is to establish general guidelines when dealing with operators
driving under the influence.
CP506 .2 ACCREDITATION STANDARDS
This procedure pertains to the following CALEA standards: 61.1.5 , 61.1.10 , 61.1.11
This procedure pertains to the following General Orders: §420, §422.5.2, §513, §514
CP506.3 PROCEDURES
CP506.3.1 DUI DETECTION OVERVIEW
The term DUI (Driving under the influence) detection has been used in many different ways.
Consequently this does not mean the same thing to all police officers. For the purpose of this
procedure , DUI detection is defined as:
THE ENTIRE PROCESS O F IDENTIFYING AND GATHERING EVIDENCE TO DETERMINE
WHETHER OR NOT A DRIVER SHOULD BE ARRESTED FOR A DUI VIOLATION.
Not all DUI offen ses are synonymous with alcoholic intoxication or alcohol impairment. There are
other types or variations of DUI that includ e, but are not limited to the following:
a) Prescription medication DUI’s ;
b) Illicit/ Illegal street drugs or narcotic DUI’s including but not limited to :
1) CNS Stimulants ;
2) CNS Depressants ;
3) Inhalants ;
4) PCP;
5) Opiates ;
6) Hallucinogens ;
7) Marijuana or Cannabis ;
The detection process begins when the po lice officer first suspects a DUI violation may be
occurring and end s when the officer decides there is or is not sufficient probable cause to arrest
a driver for DUI. That decision, ideally, is based on all of the evide nce that has come to light since
attention was first drawn to the suspect. Effective DUI enforcers do not leap t o the arrest/no arrest
decision; rather, they proceed carefully through a series of intermediate steps, each of which
helps to identify the coll ective evidence.
CATEGORY DATE ADOPTED LAST REVIEW
1 01/24/2011 11/01/201 9
TUSTIN POLICE DEPARTMENT
STANDARD OPERATING PROCEDURES
CP506 - DUI Procedure 2 CP506.3.2 DETECTION PHASES
Phase One - observe the driver operating the vehicle.
Phase T wo - after the vehicle is stopped or the subject contacted, there usually is an opportunity
to observe and speak with them face to face.
Phase T hree - administer some formal structured field sobriety tests to the driver to evaluate the
degree of impairment. A preliminary breath test may be administered in addition to field sobriety
tests to verify that alcohol is the cause of impairment.
The DUI dete ction process does not always include all three phases. Sometimes there are DUI
detection contacts i n which Phase O ne is absent; that is, cases in which there is no opportunity
to observe the vehicle in motion. This may occur at the scene of a traffic coll ision or at a safety
checkpoint. There are some DUI contacts where Phase Three never occurs. There are cases in
which formal tests would not be administer ed to the driver. These may occur when the driver is
impaired or badly injured, or refuses to submit t o tests.
CP506.3.3 MAJOR TASKS AND DECISIONS
Each detection phase usually involves two major tasks and one major decision.
In Phase One : The first task is usually to observe the vehicle in motion. Based on this observation,
the officer must decide whether there is sufficient reasonable suspicion to stop the driver. The
officer’s second task is to observe the stopping sequence.
In Phase Two : The first task is to observe and interview the driver face to face. Based on this
observation, the officer must decide whether there is sufficient reasonable suspicion to instruct
the driver to step from the vehi cle for further investigation. The officer’s second task is to observe
the driver exit and walk from the vehicle.
In Phase Three: The first task is to administer field sobriety tests . Based on these tests, the officer
must decide whether there is sufficient probable cause to arrest the driver for DUI. The officer’s
second task is then to arrange for (or administer) a preliminary breath test.
Each of the major decisions can have one of three different outcomes:
a) Yes - Do it now ;
b) Wait - Look for more additional evidence ;
c) No - Don’t do it .
CP506.3.4 DUI DETECTION
Answers to questions like the following can aid in DUI detection.
CATEGORY DATE ADOPTED LAST REVIEW
1 01/24/2011 11/01/201 9
TUSTIN POLICE DEPARTMENT
STANDARD OPERATING PROCEDURES
CP506 - DUI Procedure 3 Phase One:
a) What is the vehicle doing?
b) Are there grounds to stop the vehicle?
c) How does the driver respond to the signal to stop?
d) How does the driver handle the vehicle during the stopping sequence?
Phase Two:
a) When the officer approach es the vehicle, what d oes he/she see?
b) When the officer talks to the driver,