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SEVEN

SEVEN. The Crime Laboratory. LEARNING OBJECTIVES. Define and distinguish forensic science and criminalistics Understand the importance of an investigator's understanding of crime laboratory capabilities Describe the three measures of effectiveness of crime laboratories

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SEVEN

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  1. SEVEN The Crime Laboratory

  2. LEARNING OBJECTIVES • Define and distinguish forensic science and criminalistics • Understand the importance of an investigator's understanding of crime laboratory capabilities • Describe the three measures of effectiveness of crime laboratories • Distinguish the Frye test from the Daubert test regarding the admissibility of scientific evidence • Explain the role and importance of DNA analysis in criminal investigation • Identify the latest technologies in DNA evidence investigation and data banking • Highlight the process of fingerprint identification and comparison • Describe AFIS and IAFIS • Describe NIBIN • Briefly explain the techniques and methods used by both the ATF and FBI crime laboratories to examine evidence 7-1

  3. FORENSIC SCIENCE • Forensic science is that part of science applied to answering legal questions. It includes: • The examination • The evaluation • And the explanation of physical evidence in law 7-2

  4. CRIMINALISTICS • Criminalistics deals with the study of physical evidence related to a crime • From such a study a crime may be reconstructed • Criminalistics is interdisciplinary in nature drawing upon: • Mathematics • Physics • Chemistry • Biology 7-3

  5. UNDERSTANDING CRIME LAB CAPABILITIES • It is not unusual to find situations in which investigators not acquainted with the services of the crime laboratory expect too much from scientific analysis • The analysis of evidence can be no better than the samples submitted • The investigator therefore has a vital role to play in the success of laboratory examinations 7-4

  6. MEASURES OF EFFECTIVENESS OF CRIME LABORATORIES • The effectiveness of crime laboratories and the services performed are measured by: • Quality • Proximity • Timeliness 7-5

  7. CRIME LAB PERSONNEL • Have degrees in physical sciences • Are well trained • May testify as experts in courts (Courtesy New Jersey State Police) 7-6

  8. LOCATION OF CRIME LABORATORIES IN FLORIDA • The proximity of crime labs to the police is important • In Florida's model labs are located throughout the state • This maximizes crime lab use by the police 7-7

  9. FRYE V. UNITES STATES AND DAUBERT V MERRELL DOW PHARMACEUTICALS, INC. • Frye v. United States - the 1923 federal court decision ruling that for a scientific technique to be admissible in evidence, it must be sufficiently established to have gained general acceptance in its particular field • Daubert v. Merrell Dow Pharmaceuticals Inc. The 1993 U.S. Supreme Court decision holding that the Frye test was no longer valid in federal courts; a trial court must determine whether the testimony of an expert is based on a scientifically valid methodology and can properly be applied to the facts of the case • The application of Daubert presents a challenge to crime labs to ensure their lab results will be admissible 7-8

  10. “SNIFFING” ROBOT • Robots are used at crime scenes to: • Detect explosives • Locate drugs • Collect physical evidence (Courtesy Nashville Police Department) 7-9

  11. DNA ANALYSIS • Advances in technology have helped DNA testing to become an established part of criminal justice procedure • Questions about the validity and reliability of forensic DNA test methods have been addressed, and for the most part validity and reliability are established • As a result of DNA testing, traditional blood testing and saliva testing have been rendered obsolete • DNA is found in these substances and, if fact, is found in all body tissues and fluids • DNA evidence may be found and collected from virtually everywhere at a crime scene 7-10

  12. SOURCES OF DNA EVIDENCE • These are common sources of blood and DNA evidence that investigators need to be aware of in conducting crime scene searches. (Source: National Commission on the Future of DNA Evidence, National Institute of Justice, “What Every Law Enforcement Officer Should Know about DNA Evidence,” Pamphlet (Washington, DC: U.S. Department of Justice). 7-11

  13. DNA TECHNOLOGIES • Polymerase Chain Reaction (PCR) takes small DNA samples and reproduces many copies for analysis • Short Tandem Repeats (STRs) are smaller pieces of the DNA ladder that can be reproduced using PCR • The PCR-STR Process accelerates the analysis and typing of DNA 7-12

  14. DATABANKING AND CODIS • Today, all U.S. jurisdictions have legislation requiring the data banking of DNA evidence of convicted offenders • In addition to individual-jurisdiction data banking, there is a national investigation support database, developed by the FBI, called CODIS (COMBINED DNA Index System) • CODIS is used in the national, state and local index-system networks to link typing results from unresolved crimes with cases in multiple jurisdictions • CODIS can also be used to link persons convicted of offenses specified in the data-banking laws passed by the jurisdictions 7-13

  15. FORENSIC IDENTITY TEST • DNA may be used to: • Match victims or suspects • Eliminate suspects • Release persons wrongly convicted (Courtesy San Bernardino County, California, Sheriff’s Department) 7-14

  16. TRADITIONAL FINGERPRINT IDENTIFICATION AND COMPARISON • In the past fingerprints taken from crime scenes have been classified, filed and searched according to the Henry System • The searches of fingerprints from scenes against a Henry System file are very labor-intensive • Technological advancement since the 1970s have allowed the creation of an automated fingerprint identification process 7-15

  17. AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM (AFIS) • In the early 1970s, the FBI and the National Bureau of Standards conducted feasibility research for establishing an automated fingerprint identification process • AFIS allows law enforcement agencies to conduct comparisons of applicant and suspect fingerprints with literally thousands or millions of file prints in a matter of minutes 7-16(a)

  18. AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM (AFIS) (cont'd) • AFIS has two major duties • First is performing the functions of classifying searching and matching prints • Second is the storage and retrieval of fingerprints data • In July 1999, law enforcement agencies began to have access to the FBI’S Integrated Automated Fingerprint Identification System (IAFIA), a national on-line fingerprint and criminal history database with identification and response capabilities 7-16(b)

  19. AFIS FINGERPRINT COMPARISON • Latent prints can be searched against a file of 500,000 prints in one half hour • The system produces a list of possibles called a candidate list • Further determinations are made by a qualified fingerprint examiner (Source: Courtesy Dallas Police Department) 7-19

  20. INTEGRATED AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM (IAFIS) • The system was established by the FBI • This is a national on-line system with: • Fingerprint and criminal history databases • Identification and response capabilities • Local law enforcement began to access the system in 1999 7-18(b)

  21. INTEGRATED AUTOMATED FINGERPRINT IDENTIFICATION SYSTEM (IAFIS) (cont'd) • The local police agency must have a live-scan fingerprint terminal. The agency may then: • Scan an arrestee's prints and mug shots • Electronically transmit the prints, mug shots and personal information to their state's network for fingerprint checks • The state agency then transmits the same information to the FBI fingerprint repository for matches 7-18(b)

  22. NATIONAL INTEGRATED BALLISTIC INFORMATION NETWORK PROGRAM (NIBIN) • A joint program of the Bureau of Alcohol Tobacco and Firearms (ATF) of the Treasury Department and the FBI in the Department of Justice • The NIBIN integrates all the elements of Ceasefire and Brasscatcher, both former ATF programs and Drugfire, an FBI program • As each fingerprint is different, a firearm leaves unique identifiable characteristics on expended ammunition • NIBIN compares images of ballistic evidence, both projectiles and casings, obtained from crime scenes and recovered firearms 7-19

  23. ATF FORENSIC SCIENCE LABORATORIES • These laboratories, in addition to analyzing alcohol and tobacco samples, conduct forensic examination in support of the bureau's explosives, bombing and arson, and illegal-firearm-trafficking investigations, along with major case investigations of state and local authorities • Evidence collected at crime scenes of suspected arsons is examined to identify accelerants, incendiaries, and incendiary-device components • The bureau has four National Response Teams that respond to major bombings and arson disasters, nationally and internationally 7-20(a)

  24. ATF FORENSIC SCIENCE LABORATORIES (cont'd) • The ATF forensic labs also conduct: • Comparative trace evidence examinations • Questioned document examinations • Fingerprint, firearm and tool-mark examinations 7-20(b)

  25. THE FBI CRIME LABORATORY • The FBI crime laboratory is one of the largest and most comprehensive forensic laboratories • It provides services to state and local law enforcement without charge • Examples of lab services include: • Microscopic examinations • Chemical examinations • Mineralogy examinations 7-21(a)

  26. THE FBI CRIME LABORATORY (cont'd) • Firearms examination • Tool mark examinations • Explosives examinations • Metallurgical examinations • Handwriting and document examinations • Chemical, biological and nuclear hazards examinations 7-21(b)

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