0640.75 Polygraph Examination

Administrative Rules Adopted by Bureaus Pursuant to Rule Making Authority (ARB)
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  • ORS 163.705 Polygraph Examination of Victims in Certain Criminal Cases Prohibited
  • ORS 659A.300 Unlawful Employment Discrimination
  • ORS 703.050 Polygraph Examiner License Required ORS
  • 703.310 Polygraph Equipment Requirement
  • Title 29 USC Chapter 22 Employee Polygraph Protection Act of 1988
  • OAR 416-150-0010 Polygraph Examination of Juveniles in Custody of the Oregon Youth Authority

POLICY (640.75)

The polygraph (i.e., lie detector) is a valuable investigative tool that may be used in conjunction with, but not as a substitute for, a thorough investigation. The polygraph may be employed to verify, corroborate or refute statements, and narrow or focus investigative leads. The polygraph can assist in verifying and/or eliminating possible suspects and, in some situations, enhances the credibility of victims, witnesses, and informants.

A successful polygraph examination is dependent on a thorough investigation being conducted prior to the exam. Failure to do so may invalidate the results.

The polygrapher conducting the examination must be licensed by the State of Oregon as provided in ORS or under similar regulations in other states or federal jurisdictions. The polygraph is the only instrument for detection of deception that is authorized for use in criminal investigations and, therefore, will be the only instrument used by the Portland Police Bureau for such a purpose. Use of any other instrument purporting to be a detection of deception device is forbidden.

PROCEDURE (640.75)

Directive Specific Definitions

Exam or examination: The polygraph examination.

Polygrapher: A licensed operator of a polygraph.

Proficiency: A person skilled in the English language to understand, and be understood by other English speakers.

Subject: The person the polygraph exam is being administered to.

Appropriate use of a Polygraph Examination (640.75)

The results of a polygraph exam are admissible in court when the exam is administered:

a. In support of a warrant.

b. Is a condition of probation for sex offenders.

c. For probationary maintenance.

d. For bail hearings.

e. For suppression hearings.

f. For prison discipline hearings.

Confessions and incriminating statements obtained during these examinations may be admissible in court. The polygraph will not be used for the following:

a. Probable cause, arrest, prosecution, or withholding of property.

b. Employment purposes.

c. On employees who are the subject of an internal or criminal investigation.

1. There are exemptions to this. See the Employee Protection Act of 1988, the Portland Police Association Contract and ORS 659A.300 for details.

d. To examine sex crime victims as a condition of prosecution.

Inappropriate Polygraph Exam Subjects (640.75)

The polygraph is an instrument that records the physiological responses of a subject to the questions he/she is being asked. There are certain types of subjects who generally should not be tested due to their adverse mental, physical or emotional states.

Subjects that may be inappropriate for testing are in one or more of the following categories:

a. An I.Q. that is below 70.

b. Younger than 14 (too immature).

c. Is under the influence of drugs or alcohol.

d. Is pregnant.

e. Has a medical history that includes:

1. Being prone to seizures.

2. Respiratory illness.

3. Recent major surgery.

4. Recent serious injury.

f. Is experiencing non-chronic pain, such as a headache, and/or suffering from lack of sleep.

g. Has been involved in a lengthy interview or interrogation just prior to the exam.

h. Is emotionally involved in a traumatic incident. This would include, for example, witnessing the event, or the loss of a loved one in a homicide. A subject in this category may be rescheduled at a later date for the exam.

i. Has suffered a recent emotional shock, such as loss of a job.

Member Responsibilities (640.75)

Members wanting to schedule a polygraph exam need to contact the polygrapher at the Detective Division, who is responsible for scheduling the exam; or if the polygrapher is unavailable, the clerical staff at Detectives.

Members need to confirm that the following is completed before scheduling the exam:

a. Ensure that a thorough investigation of the crime has been done.

b. All witnesses, victims, and suspects must be interviewed prior to the exam.

1. Subjects should be interviewed in person, when possible.

2. Subjects who are scheduled for an exam must be told in advance of the exact nature of the allegations. A subject who hears the allegations for the first time at the exam could feel angered and/or alarmed. This could affect the results of the exam.

c. All reports for the case should be supplied to the polygrapher at least five days prior to the exam.

d. Subject should be advised of the following:

1. Date, time and location of the exam.

2. Exam will typically last three to four hours.

3. No attorneys or other individuals are allowed to be present during the examination.

a) Exceptions to this are at the discretion of the polygrapher, and are limited to interpreter or polygraph students.

4. The Polygrapher will explain the entire procedure to the subject at the exam appointment.

5. Subjects need to be proficient in English for the exam to be successful. A subject not proficient in English will be provided an interpreter during the exam.

a) The polygrapher should be notified in advance of scheduling the appointment if English is not the subject’s native language.

Polygrapher Responsibilities (640.75)

a. The polygrapher will administer the test.

b. The polygrapher determines when an interpreter is required.

c. The polygrapher will make all arrangements for obtaining the services of an interpreter.

d. The polygrapher will generate a special report detailing the interview with the subject and the examination results.

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