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ForensicsCHSMcNiff
Vocabulary• CRIME SCENE: Any physical location in
which a crime has occurred or is suspected of having occurred. – PRIMARY CRIME SCENE: The original
location of a crime or accident. – SECONDARY CRIME SCENE: An alternate
location where additional evidence may be found.
Vocabulary• SUSPECT: Person thought to be capable
of committing a crime.• ACCOMPLICE: Person associated with
someone suspected of committing a crime.
• ALIBI: Statement of where a suspect was at the time of a crime.
• VICTIM: a person who suffers from a destructive or injurious action or agency.
Processing Versus Analysis
Crime scene investigations have two aspects: processing & analysisProcessing follows a series of standards steps
Types of ScenesTwo major categories of criminal activities having crime scenes:
property crimes (larceny, burglary, auto theft)crimes against persons (assault, battery, sexual assault, robbery, murder)
Types of Scenes
The nature of the scene will affect the way it is handled:
indoor or outdoorpublic or private property
Initial Actions & Scene Security
Initial actions of the first responders include:
Rendering aid and assistance to the victimArresting any suspectsDetaining any witnessesNoting initial scene conditionsSecuring the scene
Initial Actions & Scene Security
Crime scene security is needed to preserve the integrity of the sceneOnce the exigent emergency situation is resolved, subsequent actions at the scene will require a warrantDuties and Responsibilities of the First Responders at the Crime Scene
Secure & Isolate the Crime Scene
First priority is medical assistance to individuals & arresting the perpetrator.Ropes or barricades and guards will prevent unauthorized access to the area. Every person who enters the crime scene has the potential to destroy physical evidence.
Secure & Isolate the Crime Scene
The lead investigator evaluates the scene & determines the boundaries. They do an initial walk through & develop a strategy.All items must be documented & photographed.
Steps in Scene Processing & Analysis
Scene Survey & Evidence RecognitionScene SearchesDocumentationEvidence Collection & PreservationRelease of the Scene
Scene Survey & Evidence Recognition
A scene survey is an initial walk-through to establish the type of scene, note any transient evidence, and recognize any potential physical evidenceTransient evidence is evidence that is easily destroyed or compromised
Scene Survey & Evidence Recognition
Evidence recognition is the determination of which physical evidence is relevant to the case as opposed to being part of the background
Systematic Search
Sketches• Once photos
are taken, sketch the scene.
Sketches• A rough sketch is a sketch, drawn at the
crime scene, that contains an accurate depiction of the dimensions of the scene & shows the location of all objects having a bearing on the case.–All measurements are made with a tape
measure–Show all items of physical evidence–Assign each item a number or letter
and list it in the legend–Show a compass heading designating
north
Rough-sketch diagram of a crime scene. Courtesy Sirchie Finger Print Laboratories, Inc., Youngsville, N.C., www.sirchie.com.
Sketches
A finished sketch is a precise rendering of the crime scene, usually drawn to scale.
Computer-aided drafting (CAD) has become the standard.
Finished-sketch diagram of a crime scene. Courtesy Sirchie Finger Print Laboratories, Inc., Youngsville, N.C., www.sirchie.com.
Notes• Note taking must be a constant activity
throughout the processing of the crime scene.
• The notes may be the only source of information to refresh memory.
• Tape-recording notes at a scene can be advantageous – detailed notes can be taped much faster than they can be written.
Searching the Crime Scene• One person should supervise &
coordinate.• Include all probable entry & exit points
in search
Searching the Crime Scene• What to search for will be determined by
the particular circumstances of the crime.– Examples
•Homicide•Hit-and-run
Ypsilanti Township, MI are looking for a burgundy vehicle in connection with a hit-and-run accident that critically injured an 11 year-old boy
Collect Physical Evidence• Physical evidence can be anything from
massive objects to microscopic traces.• It may be necessary to take custody of
all clothing worn by the participants in a crime.– Handle carefully & wrap separately to avoid
loss of trace evidence.
Collect Physical Evidence• Critical areas of the crime scene should
be vacuumed & the sweepings submitted to the lab for analysis.
• Mobile crime-scene vehicles carry supplies to protect the crime scene; photo, collect, & package evidence; & develop latent fingerprints.
Collect Physical Evidence• The integrity of evidence is best
maintained when the item is kept in its original condition as found at the crime scene.
• The entire object should be sent to the lab.
• If evidence is found adhering to a large structure, remove specimen with forceps or other appropriate tool.
Collect Physical Evidence– In the case of a bloodstain, one may either
scrape the stain off the surface, transfer the stain to a moistened swab, or cut out the area of the object containing the stain.
Collect Physical Evidence• Each different item or similar items
collected at different locations must be placed in separate containers.
• Packaging evidence separately prevents damage through contact and prevents cross-contamination.
Mock Crime Scene: http://www.masss.gov
What evidence would you collect?
fingerprints
card contains the fingerprints of Francisca Rojas, the first person convicted of murder through the taking of fingerprint evidence.
• Fingerprints latent (hidden) or visible• Fingerprints of Francisca Rojas, the first
person convicted of murder through the taking of fingerprint evidence
Post Mortem Interval
The use of post mortem changes to estimate the time of death.
Forensic pathology
Forensic pathology is a branch of pathology concerned with determining the cause of death by examination of a corpse. The autopsy is performed by the pathologist at the request of a coroner or medical examiner usually during the investigation of criminal law cases and civil law cases in some jurisdictions.
Impressions• Tire markings, shoe prints
depressions in soil, bite marks
Tool marks• The goal of toolmark analysis is to
determine if a particular tool produced a particular mark.
Hair & fibers• Any animal or human hair present
that could link a person to a crime.
Firearms & ammunition• Any firearm• Cartridge or roundPhil Spector
Glass• Particles of glass transferred to a
person or object during a crime.
• Fire Debris Analysis involves the determination of whether or not added accelerant residues are present in samples obtained from fires.
Fire Debris analyses
Explosives• Any devise containing an
explosive charge.• Also all the material removed
from the area of detonation.
World trade center bombing
Murrah Building - April 19 1995
Soil & vegetation• In forensic science, soil and vegetation
are frequently encountered as trace evidence and can be used to link suspects, cars to a crime scene
Drugs• Is any substance that, when
absorbed into the body of a living organism, alters normal bodily function
• Any substance seized in violation of laws regulating the sale, manufacture, distribution, and use of drugs
Growing Marijuana in the Basementbsapp.com
Bags for salebsapp.com
bsapp.com
Clandestine labsClandestine drug laboratories (clan labs) are facilities equipped and used in the production of illegal drugs.
Documents• Authenticating source
–Handwriting analysis
–Typewriting
– Ink
–Paper
Paint• Paint samples can be used to link
vehicles, boats,… to a crime scene• Paint transfer from a vehicle to a
struck pedestrian may be the only source of evidence linking the suspect to the crime scene.
Serology• Liquid or dried: on fabrics, objects
surfaces, …
• Can be used to determine Identity: perpetrators and victims.
• Can help reconstruct the crime.
Found on the Hike and Bike Trail in Texas
ToxicologyForensic toxicology is the use of toxicology and other disciplines such as analytical chemistry, pharmacology and clinical chemistry to aid medical or legal investigation of death, poisoning, and drug use.
Tetrodotoxin
Hemlock
X
DNA
Historical figures.How it is used to prosecute and exonerate suspects. David Vasquez, in 1989How it is extracted and analyzed.Database used by law enforcement.
Refrenceshttp://www3.sc.maricopa.edu/ajs/crime_scene_technician.htm
Bilous, Peter. Introduction to Forensic Science and Criminalistics. Washington: Eastern Washington Univesity, 5 May 2002. PPT
Pics– http://www.florida-criminal-lawyer-blog.com/2009/09/property_crime_up_in_broward_c.html– http://www.citylinks.org.uk/Images/content/84/163229.jpg
• Bug pic– http://1.bp.blogspot.com/_6QSuOepyXPE/SlJutRXLJII/AAAAAAAADPg/PEpeaUgkuyo/s400/lubber.JPG– http://thedebodeq.webs.com/apps/blog/show/prev?from_id=5880111– http://www.csialliance.org/the-basic-steps-to-become-crime-scene-investigator-career/– http://www.google.com/imgres?imgurl=http://wc1.smartdraw.com/examples/content/Examples/10_Legal/
Crime_Scene_Investigation/Crime_Scene_-_Public_Restroom_– http://www.newsday.com/long-island/suffolk/victim-s-family-asks-public-for-help-catching-killer-1.2100728– http://emt-salary.org/emt-jobs-what-you-must-know/– http://thisblogsuckssorry.blogspot.com/2011/03/things-id-rather-do-than-watch-prince.html– http://mmocker.com/2009/08/web-loot-hit-and-run-fail/– Ypsilanti Township, MI are looking for a burgundy vehicle in connection with a hit-and-run accident that critically
injured an 11 year-old boy
Pictures– http://images.townnews.com/myplainview.com/content/articles/2009/06/30/breaking_news/
doc4a42455e07bca859202760.jpg– http://www.sangeetahanda.com/newimgs/DNA_animation.gif– http://bloody2.com/images/Forward%20Spatter%206%20inch.jpg– http://www.handwritinganalysis.ca/images/013.jpg– http://www.goodcleantech.com/images/OfficeSpace.JPG– http://www.fdeservices.com/Images/tlc1.gif– http://www.designmeltdown.com/chapters/OldPaper/resources/paper_01.png– http://1.bp.blogspot.com/_Vr8Xl0cbUZA/R-fTZ4TgMcI/AAAAAAAAAmU/VADQnck9uIA/s320/Image+
%3D+Circus_Smirkus_Drug_Bust2_.jpg– http://publicsafety.com/article/article.jsp?id=1916&siteSection=14– http://nywesternfireinv.org/Gallery/Oct2007Seminar/DSC01447.JPG– http://www.nycop.com/Stories/Dec_00/World_Trade_Center_Bombing/Trade_Center_Explosion.jpg– http://www.fbi.gov/headlines/wtc400_022608.jpg– http://channel.nationalgeographic.com/staticfiles/NGC/StaticFiles/Images/Show/34xx/341x/
3415_oklahoma-city-bombing-8_04700300.jpg– http://www.nlm.nih.gov/news/press_releases/visibleproofphotos.html– http://womenofcaliber.files.wordpress.com/2009/06/ammo-101-bullet-parts.jpg– http://newsblog.projo.com/2009/03/gianquitti-tria-14.html– http://www.owlnet.rice.edu/~psyc351/Images/EdgertonBullet.jpg– http://news.bbc.co.uk/2/hi/uk_news/scotland/glasgow_and_west/5037322.stm– http://www.ccso.org/divisionsandfacilities/crimescene.cfm– http://dofs.gbi.georgia.gov/vgn/images/portal/cit_11783501/81671284trace_impressions1.jpg
Pictures– http://farm4.static.flickr.com/3054/3598094934_a254fa23b4.jpg– http://www.state.nj.us/njsp/divorg/invest/criminalistics.html– http://www.state.nj.us/njsp/divorg/invest/criminalistics.html– http://jackiemanuelsposse.files.wordpress.com/2007/07/gascan-red-copy.jpg– http://images.gamedev.net/features/art/fireParticles/fig14.gif– http://www.state.nj.us/njsp/divorg/invest/criminalistics.html– http://www.dps.state.ia.us/DCI/lab/images/toolmarks.jpg– http://www.interfire.org/res_file/images/TOOLMARK.JPG– http://www.mobio.com/images/forensics_soil.jpg– http://www.nlm.nih.gov/visibleproofs/media/detailed/ii_a_119.jpg– http://beehivehairdresser.com/wp-content/uploads/2007/12/btk.jpg– http://en.wikipedia.org/wiki/File:AlCaponemugshotCPD.jpg– http://nationalparty.us– http://www.msnbc.msn.com/id/18319872/– http://today.msnbc.msn.com/id/20997237– http://www.straightfromthea.com– http://www. aolnews.com– http://ejeuneusa.org/wp-content/uploads/2010/09/dna-double-helix.jpg– http://www.innocenceproject.org/200/ip_200.pdf
