CHAPTER Introduction Chapter Multiple Choice Forensic science is the application of science to: a Crime-scene reconstruction b Civil laws c Criminal laws d Both civil and criminal laws Answer: d Objective: Define forensic science and list the major disciplines it encompasses Page number: Level: Basic The fictional character of Sherlock Holmes was created by: a Dalton b Doyle c Darwin d Denton Answer: b Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic Who is known as the “father of forensic toxicology”? a Orfila b Locard c Osborn d Lattes Answer: a Objective: Recognize the major contributors to the development of forensic science Page number: Level: Intermediate Who developed the system known as anthropometry? a Goddard b Gross c Bertillon d Galton Answer: c Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic Who undertook the first definitive study of fingerprints as a method of personal identification? a Gross b Lattes c Locard d Galton Answer: d Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic Who devised a technique for determining the blood group of a dried bloodstain, which he applied to criminal investigations? a Lattes b Gross c Locard d Bertillon Answer: a Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic Who established the comparison microscope as the indispensable tool of the modern firearms examiner? a Goddard b Lattes c Gross d Galton Answer: a Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic Who wrote the first treatise describing the application of science to the field of criminal investigation? a Locard b Osborn c Gross d Galton Answer: c Objective: Recognize the major contributors to the development of forensic science Page numbers: 5–6 Level: Intermediate Who established the first workable crime laboratory? a Osborn b Locard c Bertillon d Galton Answer: b Objective: Recognize the major contributors to the development of forensic science Page number: Level: Intermediate 10 What is the oldest forensic laboratory in the United States? a New York City Police Department b Federal Bureau of Investigation c Secret Service d Los Angeles Police Department Answer: d Objective: Recognize the major contributors to the development of forensic science Page number: 11 Level: Difficult 11 Which entity maintains the largest crime laboratory in the world? a Scotland Yard b Royal Canadian Mounted Police c Federal Bureau of Investigation d Los Angeles Police Department Answer: c Objective: Recognize the major contributors to the development of forensic science Page number: 11 Level: Difficult 12 Which of the following would not be included in the work of the biology unit of a crime lab? a Blood typing b Comparison of hairs c DNA profiling d Fingerprint analysis Answer: d Objective: Describe the services of a typical comprehensive crime laboratory in the U.S criminal justice system Page number: 15 Level: Difficult 13 Which unit is responsible for examining body fluids and organs for the presence of drugs and poisons? a Toxicology unit b Physical science unit c Biology unit d Trace evidence unit Answer: a Objective: Describe the services of a typical comprehensive crime laboratory in the US criminal justice system Page number: 16 Level: Difficult 14 Which one of the following people did not make a contribution to forensic toxicology? a Valentin Ross b Alphonse Bertillon c Carl Wilhelm Scheele d Mathieu Orfila Answer: b Objective: Recognize the major contributors to the development of forensic science Page number: Level: Difficult 15 In Kumho Tire Co., Ltd v Carmichael, the US Supreme Court ruled that the “gatekeeping” role of a trial judge: a Was restricted to scientific testimony b Applied only to cases involving capital crimes c Was subject to appeal by a higher court d Applied to all expert testimony Answer: d Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 22 Level: Intermediate 16 The concept of “general acceptance” of scientific evidence relates to what? a Frye standard b Exclusionary rule c First Amendment d Miranda warnings Answer: a Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 20 Level: Intermediate 17 Which of the following makes a false statement? An expert witness must be able to demonstrate: a Education in his/her area of expertise b A formal degree in forensic science c Significant experience in a relevant field d Working knowledge of the subject matter Answer: b Objective: Explain the role and responsibilities of the expert witness Page numbers: 22–23 Level: Difficult 18 Who is the final evaluator of forensic evidence? a Police b Jury c Accused d Media Answer: b Objective: Explain the role and responsibilities of the expert witness Page number: 21 Level: Difficult 19 Bite marks would be least likely to be found in cases involving: a Sexual abuse b Murder c Arson d Assault Answer: c Objective: List the specialized forensic services, aside from the crime laboratory, that are generally available to law enforcement personnel Page number: 17 Level: Intermediate 20 Forensic odontology refers to the study of which of the following? a Teeth b Drugs c Bones d Rocks Answer: a Objective: List the specialized forensic services, aside from the crime laboratory, that are generally available to law enforcement personnel Page number: 17 Level: Intermediate 21 The case of Coppolino v State highlights issues dealing with what? a Search and seizure b Admissibility of the polygraph c Acceptability of new scientific tests d Warrantless searches Answer: c Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 22 Level: Difficult 22 The scientific method requires that scientific evidence be validated by what means? a Formulating pertinent questions b Formulating hypotheticals c Performing experiments d All of the above Answer: d Objective: Define forensic science and list the major disciplines it encompasses Page number: 20 Level: Intermediate 23 Which of the following services does not normally lie within the expertise of the forensic scientist? a Drug identification b Wood comparisons c Document examination d Polygraph examination Answer: d Objective: Define forensic science and list the major disciplines it encompasses Page number: 16 Level: Difficult 24 What judicial case set forth the most current guidelines for determining the admissibility of scientific examinations in the federal courts? a Frye v United States b Daubert v Merrell Dow Pharmaceuticals c Coppolino v State d Mapp v United States Answer: b Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 21 Level: Difficult 25 The effectiveness of an expert’s testimony is almost always dependent on: a The ability of the expert to talk in clear, concise language b The educational background of the expert c The scientific validity of the tests used d All of the above Answer: d Objective: Explain the role and responsibilities of the expert witness Page numbers: 22–23 Level: Intermediate 26 The dramatization of forensic science on television has led to a phenomenon known as what? a NCIS effect b NYPD effect c CSI effect d LAPD effect Answer: c Objective: Explain the role and responsibilities of the expert witness Page number: Level: Basic 27 The lay witness provides testimony that relies on what? a Scientific education b Personal opinions c Personal knowledge d Scientific experience Answer: c Objective: Explain the role and responsibilities of the expert witness Page number: 24 Level: Intermediate 28 What U.S Supreme Court case made it necessity for the forensic scientist to appear in court?: a Melendez-Diaz v Massachusetts b Crawford v Washington c Coppolino v State d Frye v United States Answer: a Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 24 Level: Basic 29 What area of forensic science examines the relationship between human behavior and legal proceedings? a Forensic psychology b Forensic sociology c Forensic pathology d Forensic psychiatry Answer: d Objective: List the specialized forensic services, aside from the crime laboratory, that are generally available to law enforcement personnel Page number: 17 Level: Basic 30 What area of forensic science is concerned with failure analysis, accident reconstruction, and causes and origins of fires or explosions? a Forensic engineering b Forensic psychiatry c Forensic anthropology d Forensic odontology Answer: a Objective: List the specialized forensic services, aside from the crime laboratory, that are generally available to law enforcement personnel Page number: 17 Level: Basic 31 The current system of crime laboratories in the United States can best be described as which of the following? a Centralized b Regional c Decentralized d National Answer: c Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 13 Level: Intermediate 32 Approximately how many crime labs are currently operating in the United States (including federal, state, county, and municipal labs)? a 250 b 400 c 150 d 200 Answer: b Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 12 Level: Difficult 33 Which of the following can be said to explain the rapid growth of crime labs during the last forty years? a Supreme Court decisions in the 1960s b A staggering increase in crime rates in the United States c The advent of DNA profiling d All of the above Answer: d Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 12 Level: Basic 34 In the case of Daubert v Merrell Dow Pharmaceuticals, Inc., the US Supreme Court advocated that a “gatekeeper” determine the admissibility and reliability of scientific evidence Who is this gatekeeper? a Expert witness b Prosecutor c Jury d Trial judge Answer: d Objective: Compare and contrast the Frye and Daubert decisions relating to the admissibility of scientific evidence in the courtroom Page number: 21 Level: Difficult 35 The eleven sections of the American Academy of Forensic Science include all of the following except: a General b Arson/explosives c Jurisprudence d Criminalistics Answer: b Objective: Describe the services of a typical comprehensive crime laboratory in the criminal justice system Page number: Level: Intermediate Chapter True-False Karl Landsteiner and Leone Lattes are associated with the area of blood typing Answer: True Objective: Recognize the major contributors to the development of forensic science Page numbers: 7–8 Level: Basic Colin Pitchfork was the first individual exonerated using DNA profiling Answer: False Objective: Recognize the major contributors to the development of forensic science Page number: Level: Intermediate Dr Walter C McCrone made significant contributions to forensic science involving microscopy Answer: True Objective: Recognize the major contributors to the development of forensic science Page number: Level: Basic The increase in crime rates in the United States has led to an increase in the number of crime laboratories Answer: True Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 12 Level: Intermediate All illicit drug seizures must be sent to a forensic laboratory for confirmatory analysis Answer: True Objective: Describe the services of a typical comprehensive crime laboratory in the criminal justice system Page number: 12 Level: Intermediate It is the responsibility of the forensic investigator to determine innocence or guilt Answer: False Objective: Define forensic science and list the major disciplines it encompasses Page number: 24 Level: Difficult The Bureau of Alcohol, Tobacco, Firearms, and Explosives is a state-run agency Answer: False Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 13 Level: Intermediate The current system of crime laboratories in the United States is decentralized Answer: True Objective: Account for the rapid growth of forensic laboratories in the past forty years Page number: 13 Level: Difficult Forensic odontologists look at bones to identify victims Answer: False Objective: List the specialized forensic services, aside from the crime laboratory, that are generally available to law enforcement personnel Page number: 17 Level: Intermediate 10 The principle of “general acceptance” comes from Frye v United States Answer: True 10 37 c 38 d 39 d 40 c 41 c 42 d 43 d 44 b 45 d 46 c 47 c 48 d 49 a 50 d 51 c 52 d 53 b 54 c 55 a 56 d 57 d 58 a 59 c 60 c 61 a 62 b 63 c 64 d 65 b 66 b True-False: True False False True True False True False False 10 True 11 True 12 False 13 True 14 True 435 15 False 16 False 17 True 18 False 19 True 20 False 21 False 22 False 23 False 24 True 25 False 26 True 27 True 28 False 29 False 30 True 31 True Fill in the Blank: Plasma Antibody Agglutinates Precipitin Seminal Aspermia DNA Genes Chromosome 10 Allele 11 Nucleotides 12 Thymine 13 Tandem 14 Amelogenin 15 Color 16 Light; color 17 Paper 18 Cloth 19 Polymerase Chain Reaction (pCR) 20 Multiplexing 21 Y-STRs 22 Microbes 23 Gene 24 Polymerases Matching: g 436 n e k a o c m d 10 h 11 f 12 j 13 i 14 b 15 l Essay: CODIS (Combined DNA Index System) is a computer software program developed by the FBI that maintains local, state, and national databases of DNA profiles from convicted offenders, unsolved crime-scene evidence, and profiles of missing people CODIS allows forensic scientists to compare DNA types recovered from crime-scene evidence to those of convicted sex offenders, other convicted criminals, missing persons, and unsolved crimes Biological evidence should not be packaged in plastic or airtight containers, because accumulation of residual moisture could contribute to the growth of DNA-destroying bacteria and fungi Articles containing biological evidence should be packaged separately in a paper bag or in a well-ventilated box • • • • Change gloves before handling each new piece of evidence Collect a substrate control for possible subsequent laboratory examinations Pick up small items of evidence such as cigarette butts and stamps with clean forceps Always package each item of evidence in its own well-ventilated container Each article of victim’s clothing must be separately wrapped and placed in a well-ventilated container Other items suspected of containing semen must be packaged in a similar manner Refrigerate the containers or store them in a cool location out of direct sunlight until delivery to the laboratory The evidence collector must handle the clothing with a minimal amount of personal contact All body fluids must be assumed to be infectious; hence, wearing disposable latex gloves while handling the evidence is required Latex gloves will also significantly reduce the possibility that the evidence collector will contaminate the evidence through perspiration 437 Care must be taken so as not to fold an article of clothing through a suspect seminal stain or to allow the stain to rub against the surface of the packaging material Have a physician or nurse collect a minimum of cc of blood from the victim and all suspects in a vacuum tube containing the anticoagulant EDTA This blood will be used for DNA and possible toxicological testing Alternatively, a buccal swab can be obtained from each individual Collect approximately 15 to 20 cut pubic hairs and 50 full-length cut head hairs from both the victim and the suspect(s) Label all evidence containers with the evidence collector’s name or initials, the date, and the sampling locations All items collected are to be described in the evidence collector’s field notes The sheet must be air-dried out of the presence of direct sunlight or heat The evidence collector must handle the sheet with a minimal amount of personal contact All body fluids must be assumed to be infectious; hence, wearing disposable latex gloves while handling the evidence is required Latex gloves will also significantly reduce the possibility that the evidence collector will contaminate the evidence through perspiration The sheet must be wrapped separately from other evidence A paper bag or well-ventilated box is recommended Refrigerate the container or store it in a cool location out of direct sunlight until delivery to the laboratory Have a physician or nurse collect a minimum of cc of blood from the victim and all suspects in a vacuum tube that doesn’t contain a preservative or anticoagulant Also, collect a minimum of cc of blood containing the anticoagulant EDTA This blood will be used for DNA testing Alternatively, a buccal swab can be obtained from each individual Label all evidence containers with the evidence collector’s name or initials, the date, and the sampling locations All items collected are to be described in the evidence collector’s field notes Critical Thinking: Blood Sample = O+ Blood Sample = AB– Blood Sample 3= A– To produce antibodies capable of reacting with drugs, the analyst first combines a specific drug with a protein and injects this combination into an animal such as a rabbit This drug– protein complex acts as an antigen, stimulating the animal to produce antibodies The recovered blood serum of the animal now contains antibodies that are specific or nearly specific to the drug • “Is it blood?”—color testing, Hemastix, Luminol, Bluestar reageant, or microcrystalline tests 438 • • “From what species did the blood originate?”—precipitin testing in a test tube or via gel diffusion “If the blood is human, how closely can it be associated with a particular individual?”— ABO/Rh blood typing and DNA profiling PCR (polymerase chain reaction) is a technique for replicating or copying a portion of a DNA strand outside a living cell Three advantages of PCR are that (1) PCR can be used with short DNA strands, (2) shorter strands are more stable and less subject to degradation than longer strands, and (3) PCR can amplify minute quantities of DNA, thus overcoming the limitedsample-size problem often associated with crime-scene evidence Combined Frequency of Occurrence = 0.21 x 0.35 x 0.09 x 0.01 x 0.11 = 0.0000073 or 7.3 x 10-6 = 0.00073% Nuclear DNA is found in the nucleus of each cell and is inherited from both parents Mitochondrial DNA (mtDNA), on the other hand, is found outside the nucleus of the cell and is inherited solely from the mother One advantage of mtDNA analysis is that it is significantly more sensitive than nuclear DNA profiling The disadvantages are that mtDNA analysis is more time consuming, and more costly than nuclear DNA profiling Also, mtDNA analysis has far less discrimating power than STRs Chapter 16 Multiple Choice: c d d b d b d a a 10 d 11 c 12 d 13 c 14 b 15 d 16 b 17 d 18 d 19 c 20 c 439 21 a 22 c 23 d 24 d 25 a 26 d 27 c 28 c 29 c 30 d 31 d 32 d 33 a 34 d 35 d 36 d 37 d 38 b 39 c 40 d 41 b 42 c 43 a 44 b 45 b 46 c 47 d True-False: False False True True True True True False True 10 True 11 False 12 True 13 True 14 False 15 False 16 True 17 True 440 18 True 19 True 20 False 21 True 22 False 23 True 24 True 25 False 26 False 27 False 28 True 29 True Fill in the Blank: Oxidation Speed Flash point Pyrolysis Spontaneous combustion Streamers Headspace Detonation Low 10 Safety fuse 11 ANFO 12 Detonator 13 Ion mobility spectrometer (IMS) 14 Acetone 15 Petroleum 16 Increases 17 Porous 18 Crater 19 Sulfur 20 Black powder 21 Blasting cap 22 Shock Matching: i d n g a k m o 441 b 10 e 11 h 12 c 13 f 14 l 15 j Essay: Nothing at the suspected origin of the fire must be touched or moved before notes, sketches, and photographs are taken All material suspected of containing flammable residues must be packaged in an airtight container, such as a clean paint can Collect two or three quarts of ash and soot debris at the fire’s origin The collection must include all porous materials suspected of containing flammable residues A portable hydrocarbon detector, as well as the evidence collector’s sense of smell, can aid in the proper selection of suspect materials Similar but uncontaminated materials from another area of the structure must be collected to serve as controls Label all specimen containers with the evidence collector’s name or initials, the date, and the sampling location All items collected are to be described in the evidence collector’s field notes • • Primary explosives are ultrasensitive to heat, shock, or friction, and under normal conditions detonate violently instead of burning Secondary explosives are relatively insensitive to heat, shock, or friction, and normally burn rather than detonate when ignited in small quantities in open air Secondary explosives are usually detonated by primary explosives • • • • • Presence of accelerants Discovery of an ignition device Irregularly shaped burn patterns on the floor or ground Streamers Separate and unconnected fires Critical Thinking: The flash point is the lowest temperature at which a liquid gives off sufficient vapor to form a mixture with air that will support combustion Once the flash point is reached, the fuel can be ignited by some outside source of temperature to start a fire The ignition temperature of a fuel is always considerably higher than the flash point The flash point of gasoline is –50ºF Therefore, the sample gasoline at –10ºF is exposed to a high-temperature igniting source, such as a match, it will ignite Hence, the suspect’s claim is untrue 442 Normally a fire tends to move upward, and thus the origin is most likely to be located closest to the lowest point that shows the most intense characteristics of burning Sometimes, as the fire burns upward, a V-shaped pattern forms against a vertical wall Because flammable liquids always flow to the lowest point, more severe burning found on the floor than on the ceiling may indicate the presence of an accelerant If a flammable liquid was used, charring is expected to be more intense on the bottom of furniture, shelves, and other items than on the top However, many factors can contribute to the deviation of a fire from normal behavior Prevailing drafts and winds; secondary fires due to collapsed floors and roofs; the physical arrangement of the burning structure; the presence stairways and elevator shafts; holes in the floor, wall, or roof; and the effects of the firefighter in suppressing the fire— these are all factors that the fire investigator must consider before determining conclusive findings Using vapor concentration, a forensic analyst can increase the sensitivity of accelerant detection at least a hundredfold over the conventional headspace technique a b c d e f Low explosive (black powder) Secondary high explosive Primary high explosive Secondary high explosive (water gel) Low explosive (chlorate mixture) Secondary high explosive (liquid explosive) Chapter 17 Multiple Choice: d a c d c b d d b 10 c 11 d 12 b 13 a 14 c 15 c 16 d 17 b 443 18 a 19 c 20 a 21 d 22 b 23 a 24 b 25 d 26 c 27 d True-False: True False True True False True False True False 10 True 11 False 12 True 13 True 14 False 15 True Fill in the Blank: Questioned document Exemplars Gilbert v California Photocopier Fax machine Impact Nonimpact Infrared luminescence Indented writing 10 Thin-layer chromatography Matching: f c h a b 444 g e d Essay: • When an insufficient number of known writings are made available for comparison • When the examiner receives questioned writings containing only a few words, all deliberately written so as to disguise the writer’s natural style Natural variations are normal deviations found between repeated specimens of an individual’s handwriting They are useful in detecting forgeries because no two specimens of writing prepared by one person are ever identical in every detail Thus, a document forged by tracing an authentic sample of writing or a signature can often be detected even if the original and the tracing coincide exactly, because no one ever writes the same words or signs two signatures exactly alike • • • • • Printing technology Type of paper Type of toner or ink used Chemical composition of the toner Type of toner-to-paper fusing method used in producing the document Critical Thinking: Individual variations may be expected in angularity, slope, speed, letter and word spacings, connections, writing skill, finger dexterity, crowding, insertions, spelling, punctuation, phraseology, and grammar The investigator cannot use the characteristics of relative dimensions of letters, alignment, margins, and spacing between lines because these characteristics are affected by the ruled or unruled nature of the paper Apparent pressure applied cannot be used because this characteristic is affected by the writing implement and paper used Objective: Know what common individual characteristics are associated with handwriting Page number: 443 Level: Difficult The sending fax machine will print a header known as the transmitting terminal identifier (TTI) at the top of each fax page The header and the document’s text should have different type styles TTIs can be fraudulently prepared and placed in the appropriate position on a fax copy, but a microscopic examination of the TTI’s print quickly reveals significant characteristics that distinguish it from a genuine TTI 445 Information about the sending individual can be gained from analysis of the letter’s spelling, punctuation, phraseology, and grammar Infrared luminescence can be used to detect alterations to a document made with ink differing from the original Infrared luminescence can also reveal writing that has been erased Indented writings are often readable when the paper is studied under oblique or side lighting A second method involves applying an electrostatic charge to the surface of a polymer film that has been placed in contact with a questioned document Indented impressions on the document are revealed by applying a toner powder to the charged film Chapter 18 Multiple Choice: d d d c b d b d d 10 b 11 d 12 d 13 b 14 a 15 a 16 d 17 d 18 c 19 d 20 b 21 c 22 c 23 c 24 d 25 d 26 c 27 d 28 d 29 c 30 d 31 b 32 a 446 33 d 34 a 35 c 36 d 37 d 38 a 39 c 40 d 41 a 42 d 43 b 44 c 45 a 46 b True-False: False False True False True True False False True 10 True 11 True 12 False 13 True 14 False 15 False 16 False 17 True 18 True 19 True 20 True 21 True 22 False 23 True 24 False 25 False Fill in the Blank: Hardware Software Central processing unit 447 Firmware Operating system (OS) Sectors Fingerprint Latent Visible 10 Swap space 11 Slack space 12 IP address 13 Random-access memory (RAM) 14 Hacking 15 Firewall 16 GPS (Global Positioning System) 17 Logical Matching: f k b i a l d e j 10 g 11 c 12 h Essay: The screen of any running computer monitor; all the connections to the main system unit, such as peripheral devices (keyboard, monitor, speakers, mouse, and so on); and equipment serial numbers • • If encryption is being used and pulling the plug will encrypt the data, rendering it unreadable without a password or key If data exists in RAM but has not been saved to the HDD, and will thus be lost if power to the system is discontinued Fragmentation is a situation in which data for the same file is contained in noncontiguous clusters on the HDD Fragmentation can degrade the performance of a HDD, causing the read/write heads to have to traverse the platters to locate the data 448 An Internet cache stores portions of the webpages a user visits on the local hard disk drive This way, if the page is revisited, portions of it can be reconstructed more quickly from this saved data, rather than having to use precious bandwidth pull it yet again from the Internet Hacking is a slang term for an unauthorized computer or network intrusion The individuals who most commonly engage in hacking are rogue or disgruntled employees who have some knowledge of a computer network and are looking to cause damage Critical Thinking: Random-access memory (RAM) stores software programs and instructions while the computer is turned on RAM is also referred to as volatile memory because it is not permanent; its contents are lost forever once power is taken away from the computer Therefore, the investigator must not automatically unplug the computer at a crime scene before data from RAM is acquired The primary goal in obtaining data from a HDD is to so without altering even one bit of data A Message Digest (MD5)/Secure Hash Algorithm (SHA) takes a “fingerprint” of a hard disk drive (HDD) before and after forensic imaging A forensic computer examiner would run such an algorithm to demonstrate that the forensic image recovered is allinclusive of the original contents and that nothing was altered in the process • Internet cache • Cookies • Internet history • Bookmarks This information tells the investigator what kind of sites a user has visited and the timeline for these visitations The investigator may learn what online news a person is interested in or what type of hobbies he or she has He or she may also see that person’s favorite child pornography or computer hacking sites recorded Additionally, considered against other evidence in the computer data, the presence of a particular cookie may have corroborative value 449