Crime Scene Investigation - Central Bucks School District

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Crime SceneInvestigationMarilyn T. MillerIntroductionFrom nanogram quantities of DNA to artificial intelligence databases capable of identifying latent fingerprints, forensic scienceand the analysis of very minute quantities of physical evidencehave advanced and improved. Yet, these applications of the scienceare remote from the crime scene and its investigation. Crime sceneinvestigation is the beginning point for the successful use of physicalevidence by the forensic laboratory and the criminal investigator.Now more than ever, the scene of a crime must always be properlymanaged and investigated in the best possible manner.Successful, high quality crime scene investigation is a simple,methodical process. It is not rigid; it follows a set of principles andprocedures that are reasonable and ensure that all physical evidenceis discovered and investigated with the result that justice is served.The basic crime scene procedures are physical evidencerecognition, documentation, proper collection, packaging, preservation, and, finally, scene reconstruction. Every crime scene isunique and, with experience, a crime scene investigator will be ableto use this logical and systematic approach to investigate even themost challenging crime scenes to a successful conclusion.Defining a Crime SceneThe only thing consistent about crime scenes is their inconsistency.Because of their diversity, crime scenes can be classified in manyways. First, crime scenes can be classified according to the location ofthe original criminal activity. This classification of the crime scenelabels the site of the original or first criminal activity as the primary crime scene and any subsequent crime scenes as secondary.This classification does not infer any priority or importance to thescene, but is simply a designation of sequence of locations.0*t93-1246-9AB/ 0.00 l.5082003 by CRC Press LLC115

116Forensic Science: An Introduction to Scientific and Investigative Techniquesi Ob ——— „ „ ———————— jp,,x Physical Evidences\ \/OUOf.krpSr

gunshot residue, etc.) are especially well suitedfor determination of credibility.Science and Crime SceneInvestigationspect.stances— The identification of unknown substancesis a common use of physical evidence.Identification of drugs, poisons, and evenbacteria such as anthrax are good examples.thefinal step in the forensic examination process.The crime scene investigator is frequentlymore interested in how a crime occurred thanidentifying or individualizing the evidence atthe scene. The "how" of the crime scene ismore important than the "who."Comparison TestingEvaluationInterpretationReporting and PresentationFigure 8.1 Steps to the scientific examination of acrime scene.

118General Crime SceneProceduresScene ManagementCrimes today are solved by the teamwork ofinvestigators and crime scene personnel andby the combined use of techniques and procedures recognizing the power of crime scenes,physical evidence, records, and witnesses.Unfortunately, numerous cases, routine andcomplex, have shown that despite availablecrime scene technologies and specially trainedpersonnel, the productiveness of a crime sceneinvestigation is only as good as the supportivemanagement team. The four distinctive butinterrelated components of1. Information management2. Manpower management3. Technology management4. Logistics managementDeficiencies, negligence, and overemphasisof any one of these components will imperil theoverall crime scene investigation. Thesecomponents are all based on the fundamentalneed for good and ongoing communicationModel TypeDescriptionFirst Responding OfficersThe first responders at a crime scene are usually police officers, fire department personneor emergency medical personnel. They are thonly people who view the crime scene in itoriginal condition. Their actions at the crimscene provide the basis for the successful cunsuccessful resolution of the investigatioiThey must perform their duties and remenber that they begin the process that links vi tims to suspects to crime scenes and musnever destroy the links.The first responders must always mailtain an open and objective mind when a]preaching a crime scene. Upon arrival, safelis a primary concern. When the scene and tlvictim are safe, the first responders mu:AdvantagesPatrol officers and detec- Useful if resources and tivesserve as crime scene demand are relatively lowtechniciansSpecially trained fulltime civilian personnelFull-time, sworn officersDisadvantages

siDie, they should initiate crime scenesecurity measures. The duties of a first responder are to:1. Assist the victim.2. Search for and arrest the suspect ifstill on the scene.3. Detain all witnesses because theypossess valuable information aboutthe crime scene. Keep witnesses separated to preserve their objectivity.4. Protect the crime scene. Begin byusing barrier tape, official vehicles, orother means to secure the scene.Establish a crime scene security logto record the names of all personswho enter or exit the crime scene. Donot smoke, drink, or eat within thesecured crime scene and do not allowunnecessary persons or officials toenter or contaminate the scene.5. Note and communicate to crime sceneinvestigators all movements andalterations made to the crime scene.Figure 8.2 Multilevel crime scene security.unwanted entries (Figure 8.2). Only in raresituations will the crime scene investigator bethe first responder. After he or she arrives, thefirst step is to evaluate the established secureareas and change them if necessary.Crime Scene SurveySecuring the Crime SceneThe Locard Exchange Principle is the basisfor linking physical evidence from or to thevictim, suspect, and crime scene. Anyone entering a crime scene can alter or change thescene and its evidence, so access to the crimescene must be restricted and, if possible, prevented except for essentiial crime scene personnel. Any physical barriers like vehicles ortapes that help protect the crime scene mustbe established as soon as possible by the firstresponders.After scene barriers have been established,one officer shall be designated as the scenesecurity officer. He or she will be responsiblefor preventing entrance into the crime scene bycurious onlookers. A contamination log orsecurity log should be kept to record allentries to and exits from secure areas of thecrime scene. Use of a multilevel securityapproach can successfully preventWhen the crime scene investigator has arrivedat the crime scene and scene security has beenevaluated, the preliminary scene survey or"walk-through" should be done. The crimescene investigator and the first responder willusually perform the scene survey together. Thelead investigator or detective, if available, canalso benefit from participating. Use of instantphotography for preliminary documentationcan be helpful. The survey is the firstexamination or orientation by the crime sceneinvestigator and the following guidelinesshould be followed: Use the walk-through to mentallyprepare a reconstruction theory thatcan and should be changed as thescene investigation progresses.Note any transient (temporary) orconditional (the result of an action)evidence that requires immediateprotection or processing.Be aware of weather conditions andtake precautions if anticipated.

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protection. Be aware of alterations orcontaminations of these areas by firstresponder personnel. Record initialobservations of who, what, where,when, and how. Assess the scene forpersonnel, precautions, or equipmentthat will be needed and notify superiorofficers or other agencies as required.sider the who, what, when, why, and how, andspecifically include: Notification information. Date andtime, method of notification, and information received.Arrival information. Means ofCrime Scene DocumentationAfter a crime scene has been evaluated by apreliminary scene survey, the crime scene'scondition must be documented (Figure 8.3).Documentation is the most important step inthe processing of the crime scene. The purposeof documentation is to permanently record thecondition of the crime scene and its physicalevidence. It is the most time-consumingactivity at the scene and requires the investigator to remain organized and systematicthroughout the process. Innovation and originality are also needed. The four major tasks ofdocumentation are note taking, videography,photography, and sketching. All four are necessary and none is an adequate substitute foranother. For example, notes are not substitutesfor photography.Documentation, in all its various forms, begins with the initial involvement of the investigator. The documentation never stops; it mayslow down, but the need for documentation remains constant. Crime scene documentationwill be discussed below in the sequence itshould follow at a crime scene. The systematicprocess presented will maintain the organizednature of scientific crime scene investigation.Taking Notes at the Crime SceneEffective notes as part of an investigation provide a written record of all of the crime sceneactivities. The notes are taken as the activitiesare completed to prevent possible memoryloss if notes are made at a later time. Accuratecrime scene note taking is crucial at pointsof entry), containers holdingevidence of recent activities (ashtrays, trash cans, etc.), clothing, furniture, and weapons present.Victim description. In most jurisdictions a body should not be moved ordisturbed until the medical examinerhas given approval, after which notescan be made of position, livid-ity,wounds, clothing, jewelry, andidentification (presence or absence).Crime scene team. Assignments toVideotaping the Crime SceneVideotaping a crime scene has become a routine documentation procedure. Its acceptanceis widespread, due to the three-dimensionalportrayal of the scene and increased availability of affordable equipment with userfriendly features like zoom lens and compactsize. Jury acceptability and expectation havealso added to the recognized use of videography in crime scene investigations.Videography of the crime scene should follow the scene survey. The videotaping of crimescenes is an orientation format. The operatorshould remain objective in recording thecrime scene. The videotape should not show

(/122Forensic Science: An Introduction to Scientific and Investigative TechniquesPhotographing the Crime Scenecific items of evidence that may be used foanalysis away from the scene. The number ophotographs that should be taken at a crimscene cannot be predetermined or limited, icrime scene investigator should never doutwhether a photo should be taken — it shoulalways be taken. Table 8.2 shows guidelinethat should be followed when photographin acrime scene.Every photograph taken at a crime seenmust be recorded in a photo log. The kshould show the time and date the photigraph was taken, the roll number, the expisure number, the camera settings (f-stoshutter speed), an indication of distance 1General or Overall PhotosMidrange Photo

Sketching the Crime SceneFigure 8.4 (A) Closeup photograph of tire tread mark insnow. (B) Closeup photograph of footwear impression inthe soil.Guidelines for Photography

124Forensic Science: An Introduction to Scientific and Investigative Techniquesgou Vi SloeJrcJnFigure 8.5 Rough sketch.Points X and Y fixed.Evidence a and b aremeasured from X and Y.tN

Digital Imaging at the Crime SceneDigital image technology provides a crimescene investigator with powerful new tools forcapturing, analyzing, and storing records ofthe crime scene and its physical evidence.These digital imaging tools complement thetraditional video and still photography used incrime scene documentation. The advantagesof digital images include instant access to theimages, easy integration into existingelectronic technologies, and no need for expensive film processing equipment and darkrooms. Disadvantages in using digital imagetechnology center on issues of court admissibility because of easy image manipulation.However, it is important to remember the investigator testifies and the image does not.Written and implemented policies and procedures for using digital images can eliminatethe disadvantages. The law enforcement community agrees that digital imaging in crimescene documentation can best be used as asupplemental technique and not completelyreplace the traditional techniques.Crime Scene SearchesThe preliminary crime scene search is an initialquasisearch for physical evidence present at thecrime scene. It is an attempt to note obviousitems of evidence and it is done for orientationpurposes before the documentation begins.After scene documentation as described above iscompleted, a more efficient and effective searchfor less obvious or overlooked items of evidencemust be done. This intensive search is donebefore the evidence is collected andpackaged. If any new items of evidence arefound, then they must be subjected to the samedocumentation tasks completed earlier.Crime scene search patterns may vary butthey share a common goal of providing organization and a systematic structure to ensurethat no items of physical evidence are missedor lost. No single method applies to specifictypes of scenes. An experienced crime sceneinvestigator will be able to recognize andadapt the search method that best suits thesituation or scene. It is important to use an established method. Simple reliance on experi-ence alone and omitting the search step in theinvestigation will produce mistakes and significant evidence can be missed.Most commonly employed search methodsare geometric patterns. The six patterns arelink, line or strip, grid, zone, wheel or ray, andspiral. Each has advantages and disadvantagesand some are better suited for outside or indoorcrime scenes. Table 8.3 summarizes thepatterns. Before any intensive crime scenesearch is done, care must be taken to instructthe members of the search party. It is temptingfor search party members to touch, handle, ormove evidence found during the search.Instruct members to mark or designate founditems without altering them. With propertraining, diligence, and care, no evidence willbe mistreated during the search of a crime scene.Found items must be documented before anyevidence can be moved or collected.The practical application of the searchmethods to the crime scene may be a combination of methods. Also, the search of a crimescene should never diminish or interfere withthe other functions of the scene investigation,including the proper documentation, collection, and preservation of the physical evidence. Do not disregard established crimescene procedures. Following chain of custodyprocedures with regard to the evidence isparamount and can be addressed by restrictingthe number of searchers for and collectors ofthe evidence.Collection and Preservation ofPhysical EvidenceAfter completion of the crime scene documentation and intensive search of the scene forphysical evidence, the collection and preservation of the evidence can begin. One individualshould be designated as the evidence collectorto ensure that the evidence is collected,packaged, marked, sealed, and preserved in aconsistent manner. No item of evidence willbe missed, lost, or contaminated if only oneperson has the obligation for

f126Geometric PatternDescriptionLink methodLine or strip methodGrid methodZone methodWheel or ray methodBest used on scenes with defined zones or areas;effective in houses or buildings; teams are assigned small zones for searching; combined withother methods; good for warrant searchesUsed for special situations; limited application;best used on small, circular crime scenesSpiral methodthis important stage in the investigation(Figure 8.8).There is no rigid order for collection of theevidence, but some types of evidence, by theirnature, should be given some priority of order.Transient, fragile, or easily lost evidenceshould be collected first. Some items ofevidence because of location within the crimescene may have to be moved or repositioned. Ifitems are moved and new evidence is discovered, documentation must proceed immediately. It is difficult to generalize about thecollection of physical evidence. Different typesof physical evidence require specific or

Figure 8.9 Proper use of primary container.Figure 8.10 Packaging of primary container insideouter container.Figure 8.11 Proper marking of sealed evidence.

128Crime Scene ReconstructionNature of Reconstruction

Case StudyrUse of Physical Evidence and CrimeScene Investigation

130Forensic Science: An Introduction to Scientific and Investigative Techniques

crime could not have occurred in the way described by the eyewitness.Shotgun Pellets and Trajectory Marks atCrime SceneA not-to-scale crime scene sketch prepared byan investigator showed the locations of variousitems of physical evidence (Figure 8.14). Thissketch reveals shotgun pellets were found inthe bedroom at locations marked 7 through10. The photographs and crime scenevideotape revealed additional shotgun pelletsand trajectory marks (Figure 8.15). The crimescene report by the note taker at the sceneshows that in the scene investigation, no shotgunpellets or wadding were found in the hallwayand that all the pellets were found in thebedroom as documented in the photographs,videotape, and sketch.Bloodstain Patterns at Crime SceneCRIME SCENE SKETCHTears in Pillowcase from Crime SceneFigure 8.14 Crime scene sketch with legend.A final piece of physical evidence documentedat the crime scene was the pillowcase removedfrom the pillow. The pillowcase was

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Marked TrajectoriesFigure 8.16pathways.Sketch of approximate trajectoryuFigure 8.17 Arterial gushfound on wall near doornside bedroom.Figure 8.19 Pillowcase showing tears caused by aglancing blast of shotgun pellets.

134Scientific crime scene investigation is the bestmethodology to ensure that an investigationis properly conducted and justice is served.Use of this methodology will prevent theabrupt end of an incomplete investigation andallow for the best use of the physical evidencefound at crime scenes.Questions1. What are the basic steps of scientific crime scene investigation?2. List and describe the definitions or classifications of crime scenes.3. What are the eight types of information that can be obtained from the examination of the physicalevidence found at crime scenes?4. What are the four components of crime scene management?5. What are the five crime scene investigation models? Describe them and give the advantages anddisadvantages of each.6. Discuss the duties of the first responder at a crime scene.7. What is the multilevel approach to crime scene security?8. What are the components or tasks of crime scene documentation? What is the purpose of each?9. What is the basic process used for photographing crime scenes? Discuss each step.10. What are the two basic types of crime scene sketches? What are the two types of perspectives used insketches?References and Suggested ReadingsATF Arson Investigation Guide (May 1997), U.S. Department of the Treasury, Washington, D.C., 1997. Bevel,T. and Gardner, R. (2002), Bloodstain Pattern Analysis with an Introduction to Crime SceneReconstruction, 2nd ed., CRC Press, Boca Raton, FL.Bodziak, W. (2000), Footwear Impression Evidence, 2nd ed., CRC Press, Boca Raton, FL. DeForest, P.,Gaensslen, R., and Lee, H. (1983), Forensic Science: An Introduction to Criminalistics,McGraw-Hill, New York. DiMaio, V. (1999), Gunshot Wounds: Practical Aspects of Firearms, Ballistics,and Forensic Techniques,2nd ed., CRC Press, Boca Raton, FL.Dix, J. (1999), Handbook for Death Scene Investigators, CRC Press, Boca Raton, FL. James, S. and Eckert, W.(1999) If Bl dE dCS2 d d CRC

cDonald, J. (1992), The Police Photographer's Guide, PhotoTest Books, Arlington Heights, 1L.cDonald, P. (1989), Tire Imprint Evidence, CRC Press, Boca Raton, FL.ational Medicolegal Review Panel (December 1997), National Guidelines for Death Investigation,National Institute of Justice and U.S. Department of Justice, Washington, D.C. gle, R. (1995), CrimeScene Investigation and Physical Evidence Manual, Vallejo, CA. edsicker, D. (2001), The PracticalMethodology of Forensic Photography, 2nd ed., CRC Press, BocaRaton, FL. taff (August 1985), Crime scene and profile characteristics of organized and disorganizedmurderers,FBI Law Enforcement Bulletin. taff (November 1995), Multi-agency response to clandestine druglaboratories, Bureau of JusticeAssistance Fact Sheet, U.S. Department of Justice, technical Working Group for Bombing SceneInvestigation (June 2000), A Guide for Explosion andBombing Scene Investigation, National Institute of Justice and U.S. Department of Justice,Washington, D.C. technical Working Group on Crime Scene Investigation (January 2000), CrimeScene Investigation: AGuide for Law Enforcement, National Institute of Justice and U.S. Department of Justice,Washington, D.C. technical Working Group on Fire/Arson Scene Investigation (June 2000), Fireand Arson SceneEvidence: A Guide for Public Safety Personnel, National Institute of Justice and U.S. Departmentof Justice, Washington, D.C.

bases capable of identifying latent fingerprints, forensic science and the analysis of very minute quantities of physical evidence have advanced and improved. Yet, these applications of the science are remote from the crime scene and its investigation. Crime scene investigation is the beginning point for the successful use of physical