SOP-38 Facial Comparison Analysis
Police Services Division
SOP-38
Issued: 10/11/2023
SUBJECT: FACIAL COMPARISON ANALYSIS
PURPOSE AND SCOPE: To establish procedures for the acceptable use of the images, information, and
tools within a facial comparison analysis system. The Rohnert Park Department of Public Safety will
utilize facial comparison analysis technology solely as a tool during investigations and active law
enforcement incidents while recognizing the established privacy rights of the public. This policy applies
to all sworn and civilian law enforcement personnel who are granted direct access to the facial
comparison analysis system as well as personnel who are permitted to request facial recognition
searches. Any outside agency or personnel from an outside agency, requesting facial comparison
analysis assistance with an investigation, must adhere to this policy.
I. BACKGROUND: Facial comparison analysis refers to an automated process of matching face images
utilizing algorithms and biometric scanning technologies. The facial comparison analysis system runs
searches against a photo database of known individuals. The system is used to identify possible
subjects who are part of a law enforcement investigation.
II. DEFINITIONS
• Facial comparison analysis technology: The automated comparison of a facial image for
the purpose of obtaining the personal identifying information (PII) of the person
depicted in the subject image, against a known person database, publicly available social
media accounts, publicly available Internet websites, and/or open-source photo
databases, resulting in a list of candidates generated by algorithmic search comparisons
used by commercial facial recognition platforms.
• Facial comparison analysis search result: An image returned by a facial comparison
analysis system that represents a potential investigative lead based on algorithmic
similarity to the submitted image.
• Identification: The action or process of identifying a person. A positive facial comparison
analysis search result is not considered a positive identification.
III. PROCEDURES
A. Facial Comparison Analysis Operation
1. Use of the facial comparison analysis system is restricted to the purposes outlined
below. Department personnel shall not use, or allow others to use, the equipment
or database records for any unauthorized purpose.
2. Facial comparison analysis shall only be used for official and legitimate law
enforcement business.
a. Facial comparison analysis shall only be used when there is reasonable
suspicion that such use will provide information relevant to an active
investigation, imminent threat to health or safety, or to help in the
identification of deceased persons or persons unable to identify themselves.
b. Facial comparison analysis may be used to assist in the identification of
missing persons that are identified as “At-Risk”.
c. Facial comparison analysis technology must be used in accordance with all
federal and state laws, and all department policies.
d. Potential matches returned by facial comparison analysis systems are to be
considered investigative leads only and shall not be used as the sole basis
for a detention, arrest, identification, or request for a warrant of any kind.
e. No employee shall verify a person’s identity based solely on possible match
results provided by the facial recognition systems.
f. Investigative searches shall only be conducted by trained Face Examiners.
Face Examiner refers to an individual who has received advanced training in
the facial comparison analysis system and its features. Examiners have at
least a working knowledge of the limitations of facial comparison analysis
and the ability to use image editing software.
3. This Procedure does not limit a Face Examiner from utilizing the facial comparison
analysis system in a proactive manner for cases being investigated by officers of this
department.
B. Prohibited Use
1. The Rohnert Park Department of Public Safety and its personnel shall not perform or
Request facial comparison analysis searches on individuals or organizations under
the following circumstances:
a. If those searches would violate applicable laws and/or other legal rights of
the individual(s) including, but not limited to, searches that are conducted
based solely on race, religion, ethnicity, citizenship, nation of origin, age,
disability, gender, gender identification, sexual orientation, or other
protected classification.
b. To assist in the identification of victims or witnesses to a criminal offense.
c. To assist in the identification of the owners of lost or stolen property.
2. Content obtained through the body-worn camera system is not to be used in
accordance with facial comparison analysis systems.
C. Reporting
1. The Rohnert Park Department of Public Safety Officer who requests the use of facial
comparison analysis software shall document positive results in an associated
report.
D. Data Retention
1. The Rohnert Park Department of Public Safety will maintain a log/audit trail of
requested, accessed, searched, or disseminated facial comparison analysis
information which will be recorded through the Facial Comparison Analysis System.
This information pertaining to facial comparison analysis requests will consist of the
following details:
• Date
• Name of Face Examiner accessing the facial comparison analysis system
• Case/Incident Number
• Authorized Purpose
• Action Name
D. Releasing Facial Comparison Analysis Data to Allied Agencies
1. The Rohnert Park Department of Public Safety shares photos stored in the facial
comparison analysis database with other law enforcement agencies upon an official
request from another law enforcement agency.
a. Facial comparison analysis data shall be available only to authorized users
for legitimate law enforcement purposes.
b. Reasonable efforts will be made to ensure the accuracy of its data.
c. Audit trails shall be maintained by each agency as defined by their policy.
2. When fulfilling an official request to share information with an allied Law
Enforcement Agency through the facial comparison analysis, the following
statement will accompany any released identification information for lead
development: “The Rohnert Park Department of Public Safety is providing this
information as a result of search, utilizing facial comparison analysis software. This
information is provided only as an investigative lead and is not to be considered a
positive identification of any subject. Any possible connection or involvement of any
subject to the investigation must be determined through further investigation and
investigative resources.”