OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

OSAC 2022-N-0025

Standard for Initial

Response at Scenes by

Scene Investigators

Crime Scene Investigation & Reconstruction Subcommittee

Scene Examination Scientific Area Committee

Organization of Scientific Area Committees (OSAC) for Forensic Science

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

Draft OSAC Proposed Standard

OSAC 2022-N-0025

Standard for Initial Response at

Scenes by Scene Investigators

Prepared by

Crime Scene Investigation & Reconstruction Subcommittee

Version: 1.0

January 2022

Disclaimer:

This OSAC Proposed Standard was written by the (subcommittee) of the Organization of

Scientific Area Committees (OSAC) for Forensic Science following a process that includes an

open comment period. This Proposed Standard will be submitted to a standards developing

organization and is subject to change.

There may be references in an OSAC Proposed Standard to other publications under

development by OSAC. The information in the Proposed Standard, and underlying concepts and

methodologies, may be used by the forensic-science community before the completion of such

companion publications.

Any identification of commercial equipment, instruments, or materials in the Proposed Standard

is not a recommendation or endorsement by the U.S. Government and does not imply that the

equipment, instruments, or materials are necessarily the best available for the purpose.

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

Foreword

This document provides standards for those who respond to scenes for the purpose of conducting

field investigations in recognizing, preserving, documenting, and collecting items of potential

evidentiary value. This document should be utilized in conjunction with local regulations to inform

or augment applicable policies.

This document does not detail the actions taken by crime scene personnel during the course of their

investigation or reconstruction of the scene. This document makes the distinction between the first

responding law enforcement officer(s) at a scene and the response of the investigative personnel.

This document has been drafted by the Crime Scene Investigation and Reconstruction

Subcommittee of the Organization of Scientific Area Committees (OSAC) for Forensic Science

through a consensus process.

All hyperlinks and web addresses in this document are current as of the publication date of this

standard.

This standard provides guidance on some safety issues but is not exhaustive. It is the responsibility

of the appropriate agency to develop a full health and safety plan.

Keywords: Crime scene, response, Crime Scene Investigator, scene investigator

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

Table of Contents

1

Scope.......................................................................................................................5

2 Normative References............................................................................................5

3 Terms and Definitions............................................................................................5

4

Requirements..........................................................................................................6

4.2 Arrival at the scene..................................................................................................7

4.3 Safety Considerations.............................................................................................7

4.4 Scene Containment & Control...............................................................................8

4.5 Legal Considerations.............................................................................................8

4.6 Assessing the

Scene................................................................................................9

4.7

Documentation.......................................................................................................9

4.8 Scene

Processing....................................................................................................9

Annex A (informative) Bibliography.....................................................................................10

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

Standard for Initial Response at Scenes by Scene Investigators

1 Scope

This document applies to the initial response of scene investigators, however named, but commonly

referred to as crime scene investigator (CSI), who responds to a scene for the purpose of conducting

field investigations and undertakes one or more of the following tasks in relation to scene

investigation: document, search for, identify, collect, interpret, and preserve evidence. This

document addresses the activities and actions required of a scene investigator when responding to

a scene and the steps to be completed prior to conducting a scene search.

2 Normative References

ANSI/ASB Guiding Principles for Crime Scene Investigation and Reconstruction.

ANSI/ASB Standard for Initial Response at Scenes by Law Enforcement.

See Annex A, Bibliography, for informative references.

3 Terms and Definitions

For purposes of this document, the following definitions apply.

3.1

contamination

The undesirable introduction of a substance to an item at any point in the forensic process. Note:

This includes undesirable transfer of a substance within an item or between items, also referred to

as cross-contamination. (ISO 21043-1)

3.2

crime scene investigation

CSI

A scene investigation that involves a potential criminal act.

3.3

crime scene investigator

CSI

An individual, however named, who is responsible for performing elements of a scene investigation

that involves a potential criminal act.

3.4

law enforcement officer (LEO)

Any public employee whose duties primarily involve enforcement or investigation of laws.

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

3.5

personal protection equipment (PPE)

Equipment worn to minimize exposure to a variety of hazards such as body-fluids, irritants, or

contaminants. Examples of PPE: gloves, foot and eye protection, respirators, and full body suits.

3.6

scene

A place or object that is subject to and/or requires forensic examination. (ISO/FDIS

21043-1:2018[E])

NOTE: A crime scene is a common description of a scene where a presumed crime has been

committed. The scene can be a person or an animal.

3.7

scene investigation

An examination of a scene to locate, document, collect, and preserve items of potential evidentiary

value. [Guiding Principles]

3.8

scene investigator

An individual, however named, who is responsible for performing elements of scene investigation.

[Guiding Principles]

3.9

scene preservation

The intentional act of refraining from any activity that may alter a scene or anything contained

within the scene. [Guiding Principles]

3.10

staging area

An area designated to be used to contain and deploy resources and conduct briefings.

3.11

walk-through

An initial visual inspection of a crime scene.

4 Requirements

4.1 ANSI/ASB Standard for Initial Response at Scenes by Law Enforcement details the

responsibilities of the initial responding law enforcement officers. The first responding scene

investigator shall ascertain what steps were taken by the responding LEO to preserve the scene in

order to maintain the integrity of the scene until designated crime scene personnel are able to

respond. The scene investigator shall seek information regarding any actions taken and any known

changes to the scene prior to the arrival of the scene investigators. Prior to arrival, if the LEO

notifies the responding scene investigator that conditions exist in the scene that could compromise

the integrity or value of evidence, the responding scene investigator shall advise the LEO what

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

mitigation, if any, should be performed. The scene investigator shall participate in a briefing with

the responding LEO upon their arrival to the scene.

4.2 Arrival at Scene

4.2.1 The scene investigator(s) should obtain or have access to, at a minimum, the following

information:

a) The initial responding and primary LEO’s names, agencies, agency identifications

(e.g., badge number), and times of arrival.

b) The primary authority for the scene (i.e. which agency is taking lead on the scene).

c) The time of the original incident, if known.

d) The conditions of the scene at the time of LEO’s arrival.

e) The size and extent of the scene including the existence of known secondary

scene(s).

f) How long the scene has been controlled and any information about access or interference

with the scene prior to it being controlled.

g) Any information regarding any alterations (e.g., items moved, disturbed, or removed) to

the scene and any movement of items at the scene between the arrival of the initial

responding LEO and the arrival of the scene investigator(s).

h) Any information concerning hazards at the scene.

i) Information from the LEO pertinent to executing the scene examination.

NOTE Attention should be taken to mitigate potentially illegitimate biasing information.

4.3 Safety Considerations

4.3.1 The scene investigator(s) shall take reasonable precautions to ensure their safety

while minimizing changes to the scene. Mitigating actions shall include, but are not limited to:

a) Ensuring the provision of designated personnel for scene security and personal safety

for all present.

b) Requesting assistance from appropriate personnel or agencies if hazards such as

chemical, radiological, biological, animal, physical, or utility (e.g. electrical or gas) are

suspected or discovered.

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

c) Wearing appropriate personal protective equipment (PPE) at all times.

d) Taking periodic breaks for rest and sustenance, especially if wearing PPE, when

outdoors, or during long periods of time on scene.

4.4 Scene Containment and Control

4.4.1 The scene investigator(s) shall review the boundaries established by the initial

responding LEO in order to determine whether the existing physical barriers are adequate or if

alterations are required. The boundaries shall enclose the furthest, immediate physical

evidence connected with the scene. Movement throughout the scene should be limited to

essential scene investigation personnel only.

4.4.2 The agency controlling the scene shall establish documentation of all personnel

entering or exiting the scene including the time of their arrival and departure and their reason

for entry. Upon arrival, if such documentation has not been started, the scene investigator shall

cause the process to begin. This log should not be the responsibility of those personnel tasked

with processing the scene.

4.4.3 The scene investigator(s) shall ensure that a path for authorized personnel to enter

and exit the scene has been established and is appropriate for the preservation of evidence

integrity.

4.4.4 The scene investigator(s) shall ensure that a staging area is designated. The staging

area may be located in any secured area (e.g., vehicle, trailer, tent, or within a building). The

staging area should be positioned outside of present or potential hazard zones but close enough

to the incident to maintain command and deploy response resources in an efficient manner.

4.4.5 The scene investigator(s) shall establish an area designated for trash, e.g. biohazards,

other hazardous materials, and used supplies. If it is not practical to place this within the

staging area, an area shall be carefully chosen within a confined portion of the scene. If this

area is established within a scene, the scene investigator shall ensure the designated area has

been documented, searched, and deemed safe to assume that role. All items secured therein

shall be confined to the area, contained within an appropriate receptacle, and collected upon

departure from the scene.

4.4.6 The scene investigator(s) shall establish a secure area on scene for the temporary

storage of evidence following initial collection in accordance with preserving evidence integrity

and chain of custody.

4.5 Legal Considerations

4.5.1 The scene investigator(s) shall conduct themselves with the expectation that their

work may be used in every step of the legal process, and therefore shall ensure that they

comply with applicable legal standards including those of search and seizure.

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

4.6 Assessing the Scene

4.6.1 The scene investigator shall conduct a preliminary scene evaluation that should

include initial observations and information obtained from the responding LEO(s) to determine

appropriate resources and response.

4.6.2 The scene investigator shall conduct a scene assessment (also known as a

“walk-through”) using appropriate precautions, to obtain an overview of the entire scene,

identify any hazards or threats to scene integrity, and ensure the protection of physical

evidence, unless doing so would compromise safety or the potential evidence. The assessment

should encompass time, conditions, life, property, personnel and any pertinent information

relative to the incident.

4.6.3 The scene investigator shall use the scene assessment to develop a plan for the

coordinated identification, collection, and preservation of evidence. The plan should be

reassessed as appropriate to address such things as new information, changes in scene

conditions, and new material located at the scene. This includes the consideration of the

existence of multiple scenes.

a) Measures shall be instituted to preserve and protect evidence that may be lost or

compromised due to environmental conditions or the nature of the evidence item. Such

measures may include prioritized collection or use of protective measures that also prevent

contamination, tampering, alteration, or loss of evidence.

b) There may be the need for immediate documentation and collection of evidence prior to the

full completion of the scene assessment to prevent contamination, alteration, or loss of

evidence.

4.6.4 The scene assessment shall also be used to determine the need for specialized

reconstructive efforts or additional resources.

4.7 Documentation

4.7.1 The scene investigator(s) shall document all pertinent information and observations

including but not limited to the conditions of the scene and the investigative steps taken,

providing a permanent record.

4.8 Scene Processing

4.8.1 Information gathered during the initial scene response and assessment shall determine

the actions taken by the scene investigator in processing the scene. The information-gathering,

observation, and assessment processes are cyclical and shall be repeated and revised as necessary

throughout the entirety of scene processing.

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OSAC 2022-N-0025 Standard for Initial

Response at Scenes by Scene Investigators

Annex A

(informative)

Bibliography

1] National Forensic Science Technology Center. Crime Scene Investigation: A Guide for Law

Enforcement [supported under cooperative agreements by BJA, NIJ, and NIST]. NFSTC, 2013.

https://www.nist.gov/sites/default/files/documents/forensics/Crime-Scene-Investigation.pdf

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2] Federal Bureau of Investigation. Standard ERT 12-Step Process. Undated.

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3] ISO 21043-1:2018(E) Forensic sciences- Part 1: Terms and definitions, 2018.

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4] ISO/FDIS 21043-2:2018(E) Forensic sciences- Part 2: Recognition, recording, recovery, transport

and storage of material, 2018.

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International Organization for Standardization, 1, ch. de la Voie‐Creuse, Case postale 56, CH‐1211 Geneva 

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International Organization for Standardization, 1, ch. de la Voie‐Creuse, Case postale 56, CH‐1211 Geneva 

2 Federal Bureau of Investigation, 935 Pennsylvania Avenue NW, Washington, DC 20535

1 National Forensic Science Technology Center. 8285 Bryan Dairy Rd #125, Largo, FL 33777

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