List the steps taken to preserve a crime scene
What does the term ARISN stand for? (First responders)
Approach, render medical aid, identify additional victims or witnesses, secure the scene and physical evidence, notifications.
Approach (first responders)
Approaching the scene be observant Scan for suspicious things or persons Be alert to evidence, witnesses and victims Call for more help if needed Upon arrival. Preserve the scene with minimal contamination Approach the scene cautiously. Noting vehicles and people Make observations... look, listen, and smell Observe weather, temp, and time of day
Crime scene safety include...
Be cautious with sharp objects Be cautious of bio/Chen hazards Search small areas with a flashlight and mirror Decontaminate equipment with bleach or alcohol Wash hands often
PPE (personal protective equipment)
Designed to protect you from getting contaminated from the scene and protecting the scene from becoming contaminated by you. Includes... gloves (chem resistant) Safety masks- dust mask, respirator, SCBA disposable coveralls: Tyvek Booties Head protection Air monitoring equipment - gas and radiation monitors
Secure the scene (first responders)
Identifying, establishing, protecting, and securing the boundaries- Where the crime occurred Points of exit and entry of the suspects Locations where victims and evidence may have been or moved to ***always set the initial boundary/perimeter larger than the scene. Make multiple boundaries for media, chain of command (command post) neighbors. Establish a perimeter- Yellow tape Barriers (natural/man made) Ropes Vehicles Cones Personal Protecting the scene by documenting all actions and observations- State of scene Existing conditions Personal info of victims and witnesses Need to know who enters and exited the scene and for what reasons Actions and statements of persons entering and exiting must be recorded - there may be a need for know (elimination) samples from personnel I.e. Fingerprints, DNA, shoe prints If items If items are moved you need to know which items and who moved them to where they were moved (maintain control) Once the boundary is secure minimize who enters and exits Keep unauthorized individuals from entering Maintain a log of who enters and exits Establish some sort of command and control point (command center) Crowd control (area for crowds and media) Locate and establish a location for equipment If long and protracted scene a location for rest and recovery must be established Establish a decontamination zone.
Notifications (first responders)
Request additional personnel Multi jurisdiction support Other government agency involvement Identify family members, etc.
Rendering medical aid (first responders)
Safety, physical security, and well being of victims, witnesses, public, and first responders is crucial (TacMed) Mitigate the threat(active shooters, fire, explosions, unstable buildings) If the crime scene becomes contaminated while rendering aid... so be it. Take all steps to maintain control. Identify and control dangerous situations or persons Continue to scan for sights, sounds, and smells
Why are single entry points and exit important at crime scenes?
To prevent contamination, prevent degradation of evidence, and maintain chain of custody.
Identify witnesses/victims (first responders)
Witnesses identify suspects and locations of additional evidence Separate the witnesses so they don't cross contaminate stories Be observant if witnesses give identical stories- they may have collaborated before police arrived.
