44.493 Issues in Criminal Justice and Technology

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• DNA Analysis
  "DNA analysis is probably the most powerful investigative tool in law enforcement today. It is the perfect criminal justice system. Performed correctly, DNA analysis is impartial and infallible. It does not discriminate between good guys and bad. It ignores loopholes in the legal system, and persuasive arguments by the defense. It is exquisitely simple and unbelievably complicated. And in its brief tenure in the forensic sciences, it has incited more controversy, faced more legal challenges, and sparked more hope than any other technique in law enforcement history. " (my emphasis) FBI's crime laboratory, which does much of the nation's DNA analysis, has estimated that it needs a blood stain at least the size of a dime, and a semen stain the size of a pencil eraser for single-site testing. When the specimen is smaller, it is almost impossible to test more than one site because not enough of the sample is available. "DNA analysis has had to fight its way through the courts and through the skepticism of the legal community, for acceptance. The science itself has been taken to task, as have testing protocols, the astronomical numbers that result when calculating match frequencies, and how those matches should be interpreted. National Academy of Science study in 1992: DNA Technology in Forensic Science, said it "strongly supported the validity of DNA testing." (Appendix Fifteen describes how DNA analysis cleared some legal hurdles.)
  • National Institute of Standards and Testing (with NIJ funding) developed Standard Reference Material (SRM) 2390containing a set of materials to be used when doing RFLP analysis. It "enables forensic scientists to ensure right answers and pinpoint when and where mistakes are made. The standard also lets labs show that its daily working standard is traceable to NIST, which is important if lab results or test protocol are challenged in court."
  • Population genetics used to challenge DNA analysis. At lst, statistics based on a small sample of population. Defense attorneys demanded proof techniques were valid and could be applicable to all racial and ethnic groups. Under an NIJ grant, Dr. Ranajit Chakraborty, of University of Texas Health Science Center's Graduate School of Biomedical Sciences, built database by collecting DNA samples from about seventy populations around the world, and developed analytical methods to test the data. Used this information to develop standards for computing match probabilities (has resulted in some interesting findings, including identifying 9/11 victim)
  • 1996 NAS report concluded advances in knowledge and technology meant that "In the not distant future, distinguishing even close relatives like brothers will be routine, and DNA profiles will be treated much as fingerprints are today," and "DNA evidence, when properly collected and analyzed, should not be called into question." "The NAS committee of 11 scientific and legal experts stressed that investigators and crime scene technicians use meticulous care in gathering evidence and in maintaining the chain of custody. The committee suggested that evidence be divided into two parts, with one set aside for testing by a second laboratory if requested by the defense. It also advised crime labs to seek accreditation for DNA analysis by the American Society of Crime Lab Directors.
    • On one hand, DNA is being used to identify tsunami victims. On the other, civil libertarians believe ithe Mass. State Police effort to take samples from every man in Truro to solve a murder is an invasion of privacy.
• Photography
  "Perhaps the best way to give a jury an accurate image of a crime is with pictures. Photographs cut through pre-conceived notions or false interpretations a juror may have from listening to an oral description. They can be stored almost indefinitely, providing the investigator with a visual record of the crime scene. Photography provides the permanent record, and with today's sophisticated computer technology, crime scene photographs can be turned into a digital record that will outlive even the lengthiest of appeals." (my emphasis) New advances:
  • "Louisiana researchers found a way to enhance the photographic image of injuries of human skin by extending the technologies of reflective and fluorescent ultraviolet imaging. Their research produced pictures of wounds and marks that are invisible to the naked eye and are as old as six months. Their techniques have been especially effective in cases of child abuse, and have helped clear several murder cases."
  • NIJ funded researchers in New York to develop computer program called "Restoretool," to enhance blurred, grainy or poorly contrasted photographs.
  • NIJ's National Law Enforcement and Corrections Technology Center West using computer to make the enhance images in photographs from ATM machines and security cameras.
• Video cameras:
  mounted in squad cars, used at crime scenes, academies use for simulations andtraining, investigators use them for surveillance.
• Firearms
  Ballistics examiner uses comparison microscope to match characteristics from a spent shell casing with the weapon from which it was fired. Advances:
  • "NIJ-funded grant resulted in a computer sourcebook to help firearms experts identify different types of weapons and ammunition." Written in hypertext, it lets examiners point and click their way to more in-depth research, enables them to do trajectory analysis, and helps them prepare cases for court.
  • National Integrated Ballistics Information Network, a joint project of FBI and ATF, tracks ammunition to solve crimes.

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