Final Exam Review PDF

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FINAL EXAM REVIEW for the final exam in the course Crime and Forensics taught by Professor Forsthoff. ...

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Crime & Forensics Final Exam Review  ● Crime Scene ○ The area where a crime may have occurred. The area is established by the investigator in charge, but must encompass the crime-related activities. ● Crime ○ An offense against the public at large, proclaimed in a law, and punishable by an official governing body. ● Forensic(s) ○ Pertaining to, connected with, or used in courts of law or public discussion and debate. ○ Adapted or suited to argumentation; rhetorical. ○ The art or study or argumentation and formal debate. ● Forensic Science ○ A discipline compromised of a diverse group of forensic professionals who employ and adhere to the rigorous standards of their respective professions, who consider matters under consideration in order to ascertain the truth of a set of alleged facts, criminal or civil. ● Evidence ○ Anything offered in court to prove the truth or falsify of a fact in issue. ● Crime Scene Investigation (CSI) ○ The beginning point for the successful use of physical evidence by the forensic laboratory and the criminal investigator. ● Investigation Process ○ Recognition ■ Scene survey - “walk through” ■ Documentation - notes, photos, sketches, videos. ■ Collection and Preservation of Physical Evidence - systematic “scene search” ○ Identification ■ Comparison testing. ○ Individualization ■ Evaluation and interpretation. ○ Reconstruction ■ (determining/eliminating events) ■ Reporting and presentation. ● Pictorial Documentation ○ One of the investigator’s most important jobs at the crime scene is to create an accurate, objective, visual record of the crime scene before any items or objects are moved or removed as possible elements of evidence. ○ Photos of the scene of a serious criminal act should be taken as soon as possible after preliminary investigative priorities have been taken care of, and before note taking, sketching, or a search for evidence begins.

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Evidence ○ Anything offered in court to prove the truth or falsity of a fact in issue. The Forensic Mind ○ If a man will begin with certainties, he shall end in doubts; but if he will be content to begin with doubts, he shall end in certainties. Evidence Types ○ Testimonial ○ Real or physical ○ Demonstrative ○ Documentary ○ Direct ○ Circumstantial Testimonial ○ Spoken evidence concerning facts personally observed or experienced by witnesses sworn to testify. Real or Physical ○ Tangible objects in their original state. To show fact about them which is relevant to an issue in the case. Demonstrative ○ Photographs, diagrams, maps, to show or help illustrate some fact which is relevant. Documentary ○ Written evidence. Direct ○ Evidence directly perceived by the five senses. Circumstantial ○ Evidence based on an interference we make as to the existence of unobserved fact from our knowledge of the existence of certain other facts that have been proved. Rule of Evidence ○ Rules of court that govern the admissibility of evidence at trials and hearings. ○ Exclusionary rule ○ Relevancy (materiality) ○ Competency Exclusionary Rule ○ Evidence that has been obtained in violation of constitutional guarantees against unlawful search and seizure must be excluded at trial. Relevancy (Materiality) ○ The applicability of evidence in determining the truth or falsity of the issue being tried. Competency ○ The quality of a piece of evidence and/or a person offering evidence. Physical Evidence

Anything detectable by sensory, physical, chemical, optical or electronic means, including those things in a digital or multimedia form, that provide factual information about a crime. What can Physical Evidence Reveal? ○ Corpus Delecti - B  ody of the Crime. ○ Modus Operandi - M  ethod of Operation. ○ Linking Of: s uspect with victim; person to crime scene. ○ Disproving/Supporting t estimony ○ Identification o  f suspect(s) ○ Providing I nvestigative Leads Physical Evidence Collection ○ The entire success of a criminalistic operation, as it is concerned with physical evidence, depends on: ■ Receiving all relevant evidence ■ Proper condition of evidence for examination ■ Establish origin and chain of possession (custody) of evidence. Chain of Custody ○ Proof of possession of evidence from the moment it is found until the moment it is offered as evidence. Physical Evidence Preservation Procedure: ○ Recognize relevant physical evidence. ○ Determine that it can be tested in a lab. ○ Collect with care and diligence. ○ Handle, package and label properly. ○ Record recovery; photographs, sketch, notes. ○ Chain-of-custody; scene to lab to court. ○ Present or explain in court. Physical Evidence Characteristics ○ Class Characteristics ○ Individual Characteristics Class Characteristics ○ Describe the physical object and limit the likelihood that similar objects exist. Individual Characteristics ○ Those which make an object different from all others within its group, establishing the unique identity of an object to the exclusion of all others. ○ Fingerprints ○ Teeth marks ○ Firearms ○ Spent ammunition ○ Tools ○ Toolmarks ○ Typewriting ○ Shoe prints ○

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○ Tire tracks ○ Handwriting ○ DNA typing. Individualization Principle ○ All objects in the universe are unique. ○ No two things that happen by chance ever happen in exactly the same way. ○ No two things are ever constructed of manufactured in exactly the same way. ○ No two things ever wear in exactly the same way. ○ No two things ever break in exactly the same way. Individualization ○ The individualization of an impressions [fingerprint, dental, shoe, bullets, handwriting, break/fracture] is established by finding agreement of corresponding individual characteristics by such number and significance as to preclude the possibility (or probability) of their having occurred by mere coincidence, and establishing that there are no differences that cannot be accounted for. Types of Physical Evidence ○ Weapons (guns, knives, clubs, cordage) ○ Tools (all marks made by them) ○ Projectiles (bullets, cartridges, shell cases) ○ Materials ( glass and paint fragments, bits of metal and plastic) ○ Prints (fingers, shoes, tires, tools) ○ Clothing (fibers, stains, contact traces) ○ Physiologicals ( blood, semen, saliva, other fluids, tissues, and hair.) ○ Blood and Tissue ( toxicological analysis) ○ Motor Vehicles (anything) ○ Fire Residues ( accelerant containers, debris) ○ Drugs (pills, capsules, tablets, powders, residues) ○ Questioned Documents (handwritings, handprinting, typewriting, printers, mechanical and thermographic reproductions, obliterations, inks, papers, folds.) ○ Digital ( computers, cell phones, thumb drives, MP-3’s, cameras, copiers, printers, any storage devices (cards), etc.) Stages of Analysis ○ Recognition ○ Documentation ( scene and evidence) ○ Collection and Packaging ○ Preservation ○ Analysis (identification, individualization, reconstruction) ○ Interpretation of Results ○ Reporting Results and Expert Testimony. Purpose of Crime Laboratory

To provide the investigator with answers to questions related to the identity of the evidence and how the evidence might relate to the elements of the crime and its predators. Forensic/Crime Laboratory ○ A laboratory, with at least one full-time scientist, which examines physical evidence in criminal matters and provides opinion testimony with respect to such physical evidence in a court of law. Operations of Crime Laboratory ○ Public and Private ○ Federal (FBI, ATF, DEA, USPS, USSS, USEPA) ○ State (NJSP Regional Laboratory System - North, East, Central, South) ○ Local (County: Hudson, Cape May, Union, Ocean) ○ Municipal (Newark) Crime Laboratory Role in Society ○ Responsibility to the police ■ Effective communications regarding case analysis of physical evidence with “integrity,” scientists must remain “objective” and not view themselves as instruments of the police. ○ Responsibility to the prosecution. ■ Quality and reliable analysis as an expert witness: an unbiased scientist beyond reproach - “Impartiality” ○ Responsibility to the victim. ■ Obligation to perform comprehensive analysis of evidence. ■ Must remain “object” and not align themselves too closely; can not overstate conclusions to assist with prosecution. ○ Responsibility to the suspect/defendant. ■ Identify the guilty … identify the innocent. ■ Obligation to provide results expeditiously. ○ Responsibility to society. Fingerprints (Friction Ridge Skin) ○ Hairless ○ Contains no sebaceous (oil) glands ○ Much higher concentration of nerve endings. ○ Much higher concentration of sweat glands. ○ Lacks pigmentation. ○ Exists only on palm side of hand and sole of feet. ○ Designed for grasping, holding and feeling. Fingerprints Residue ○ Skin Surface Residue (Eccrine, Sebaceous, Keratinizing, Epidermis, Apocrine) ○ Deposition (time, pressure, contact angle) ○ Donor (child, adult, gender, age, health, diet) ○ Substrate (porous, non-porous) ○ Containments (outside materials/chemicals) ○

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○ Ambient Conditions & Time (light, temperature, moisture and humidity) Types of Evidentiary Fingerprints ○ Three types of fingerprints encountered at crime scenes or on evidence: ■ Patent ■ Plastic ■ Latent Patent Fingerprint ○ Clearly recognizable fingerprint that needs no processing - could be in grease, blood, dirt, or oil. Plastic Fingerprint ○ Also called an impression or indentation print - could be in tar, butter, silly putty. Latent Fingerprint ○ Requires additional processing to be rendered suitable for comparison - processing is called development or enhancement. General Fingerprint Patterns ○ Loops (60%, ulnar, radial) ○ Arches (5%, plain, tented) ○ Whorls (30%, plain, central pocket, double-loop, accidental) Fingerprints Comparison: A.C.E.-V ○ General Pattern Agreement ( class characteristic - loop, whorl, arch) ○ Qualitative Concordance (ridge characteristics - same type and shape) ○ Relationship of Ridge Characteristics (various details must stand in same relationship) ○ Quantitative Factors (number of points (minutiae) shared by two impressions) A.C.E.-V ○ Analysis ○ Comparison ○ Evaluation ○ Verification Fingerprint Analysis ○ The qualitative and quantitative assessment of level 1 (pattern), level 2 (ridge characteristics), level 3 (pore characteristics, scars, edgoscopy for example. Details to determine their proportion, interrelationship and value to individualize. Fingerprint Comparison ○ To examine the attributes observed during analysis in order to determine agreement or discrepancies between two friction ridge impressions. Fingerprint Evaluation ○ The cyclical procedure of comparison between two friction ridge impressions to effect a decision. Fingerprint Verification ○ An independent analysis, comparison, and evaluation by a second qualified examiner of the friction ridge impressions.

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Major Ridge Patterns ○ Major ridge path formations are sometimes referred to as: ■ Ridge Endings - r idges that end abruptly ■ Bifurcations - R  idges that appear to split apart and continue on as two ridges ■ Enclosures - Ridges that appear to split in two and then rejoin. ■ Short Ridges - C  onsist of at least two ridge units. ■ Ridge Dots - o  nly one ridge unit. Fingerprint Development Methods ○ Physical - p  owders - various colors; technical; inked - Live and Dead. ○ Chemicals - I odine fuming (reacts w/fats & oils); Ninhydrin (reacts w/ amino acids); Silver Nitrate (reacts w/ salts); Cyanoacrylate ‘Super Glue’ vapors. ○ Light - L  ASER, U.V., Alternate Light Source. Firearms Identification ○ A discipline of forensic science which has as its primary concern to determine if a bullet, cartridge case or other ammunition component was fired by a particular firearm. Ballistics ○ The study of the motion of a projectile. Rifles ○ A firearm with a rifled barrel, designed for use with two arms and fired from the shoulder. Shotguns ○ A shoulder fired smooth-bored firearm. Handguns ○ A short firearm with a rifled barrel intended to be aimed and fired with one hand. Semi-automatic Pistol ○ A self-loading handgun which fires, ejects the empty cartridge case, reloads and cocks itself each time the trigger is pulled. Revolver ○ Repeating handgun with a revolving cylinder chambered to hold cartridges, can be single or double action. Derringer ○ Small, easily concealed handgun, with 1-4 barrels each firing a single shot. Range Determination ○ Distant Shot - s hot fired from such a distance that no gunshot residue reached the target surface. ○ Close-range Shot - s hot fired close enough for some gunshot residue to reach target surface. ○ Near-Contact Shot - s hot fired a range of 1” or less. ○ Contact Shot - s hot was fired with the muzzle in contact with the target surface. ■ Loose contact - j ust touches surface, gases may escape. ■ Hard contact - p  ressed tightly, gases follow bullet. Firearm Lab Examination

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○ Identify and compare fired bullets and cartridges ○ Examine powder and shotgun pellet patterns. ○ Restore obliterated serial numbers. ○ Conduct toolmark examinations. Firearms Examiner Conclusions ○ Positive Identification - t he questioned firearm fired the questioned bullets and/or cartridges. ○ Negative Identification - t he questioned firearm did not fire the questioned bullet and/or cartridges. ○ Inconclusive - t he questioned firearm could have fired the questioned bullets and/or cartridges. Trace Evidence ○ Physical evidence that results from the transfer of small quantities of material - hair, textile fibers, paint chips, glass fragments, gunshot residue particles. Fiber Type ○ Animal Hairs - p  resence of scales: wool, goat, silk, camel, llama, rabbit, cow. ○ Plant Fibers - s eed, bast, leaf, fruit, cotton. ○ Mineral - g  lass, wool, asbestos. ○ Man-Made Fibers - r egenerated and synthetic: acrylics, nylons, polyesters. Class Characteristics ○ Density - mass/volume. ○ Refractive Index - difference, or ratio of velocity of light in a vacuum and its velocity through glass determines degree of refraction. Individual Characteristics ○ Broken pieces, glass fracturing. Internal Computer Crimes ○ Alterations to computer programs that result in the performance of unauthorized functions within a computer program. Telecommunications Crimes ○ Illegal access to or use of computer systems over telephone lines. Computer Manipulation Crimes ○ Changing data or creating records in a system for the advancement of another crime, usually theft related. Support of Criminal Enterprises ○ Data bases to support - drug distributions, records of client transactions, money laundering. Hardware and Software Thefts ○ Thefts of computers, microprocessor chips, trade secrets, witnessed software piracy. Cyberspace Online Crimes ○ Committed in the world of online computer communications - World Wide Web (WWW), Usernet, Newsgroups, Internet Relay Chat rooms and Electronic Mail (E-mail).

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Document ○ Any fixed method of communication between one individual and another. Questioned Document ○ One that in its entirety or in part is suspect as to authenticity or origin. Forged ○ Documents that are altered originals produced by adding, removing or substituting relevant information or features. Counterfeit ○ Documents that are reproduced as originals. Sources of DNA ○ Blood (white blood cells), tissue, hair root, urine, semen, bone, saliva, tooth pulp. DNA Typing Systems ○ RFLP (Restriction Fragment Length Polymorphism) ■ Determines variation in the length of a defined DNA fragment; requires more and better quality DNA. ○ PCR (Poulmerase Chain Reaction) ■ A general technique for increasing the amount of a specific section of DNA in the sample, DNA amplification; results may be obtained for a sample of limited quality and quantity. Semen ○ A semi-fluid heterogeneous gelatinous mass; produced by post-pubescent males and ejaculated following sexual stimulation. Saliva ○ A slightly alkaline secretion found in the mouth. Its primary purpose is to aid in the initial stages of digestion by lubricating food masses for easier swallowing and initiating the digestion of starches using the enzyme amylase. Passive Stains ○ Move only under the influence of gravity. Spatter Stains ○ Arise from a force in addition to gravity. Altered Stains ○ Physically or physiologically changed. Forensic Pathology ○ Involves the examination of living and dead people and the analysis of biological and physical substances in order to provide opinions concerning: ■ The cause, mechanism, effects, and manner of injury, illness or death. ■ The identification of people. ■ The nature and significance of biological and physical evidence. ■ The correlation and/or reconstruction of wounds. ■ Patterns, and sequences. ■ Investigating and documenting the mechanisms of disease and injury. Medicolegal Death Investigation ○ Scene of death investigation.

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○ Witness gathering. ○ Documentary evidence - social, psychiatric, medical history of deceased. ○ Postmortem examination and autopsy. ○ Report. Role in Forensic Death Investigation ○ Ascertain that death has occurred. ○ Establish identity of deceased. ○ Identify place of injury and place of death. ○ Estimate time since death. ○ Establish whether body has been moved since death. ○ Obtain evidence from body that may be lost or will deteriorate during transport. ○ Formulate sequence of fatal events and surrounding circumstances. ○ Establish diagnosis of apparent cause and manner of death. Cause of Death ○ The injury or disease which initiates the chain of events leading to death. Mechanism of Death ○ The biochemical or physiologic abnormality produced by the cause of death which is incompatible with life. Manners of Death ○ Natural - d  eath resulting from the inevitable failure of a vital body function due solely to a natural disease process. ○ Accidental - d  eath due to trauma but the trauma was not intentionally applied to the body. ○ Suicidal - d  eath due to trauma which is intentionally self-induced. ○ Homicidal - a third party intentionally causes the injuries leading to death - not necessarily unlawful. ○ Undetermined - i ndicators that are so equivocal. Toxicology ○ The study of poisons (toxins or toxicants) that can cause impairment, poort health, or death. Forensic Toxicologist ○ Concerned with the recognition, study, and evaluation of foreign chemicals by the analysis of body fluids, tissues, organs, and materials originating from living organisms. Postmortem ○ To determine whether alcohol, drugs or other poisons may have caused or contributed to the death of a person. Human Performance Testing ○ Deals primarily with driving under the influence of drugs and alcohol, can also be referred to as behavioral toxicology dealing with an inability to per...