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CRIMINAL INVESTIGATION Forensic Chemist-Criminologist
THE ART & SCIENCE Of CRIMINAL INVESTIGATION ARLYN M. DASCIL-CANETE Forensic Chemist-Criminologist PNP Crime Laboratory
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Criminal investigation and detection
Criminal investigation and detection is both an art and a science; a collaboration of common sense, judgment, intellect, experience and an innate intuitiveness along with a grasp of relative technical knowledge. Hence, Technological advances have been incorporated into criminal investigation; thus, if there is reason to assume that a crime has indeed been committed, further investigation is undertaken using Scientific methods and techniques.
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Three tools or 3i’s in Criminal Investigation
(1) Information, (2) Interrogation, and (3) Instrumentation Information – is the knowledge of the investigator gathered and acquired from other persons, or various sources including the victim himself, and from private records and modus operandi files. Interrogation – is the process of questioning witness and suspects to obtain further information. Instrumentation - is the application of instruments and methods of physical science for the detection
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Remember: Criminal investigations are conducted in accordance with the dictates of the law. The conduct of an investigation is governed by information obtained from: people, records, and physical evidence
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Criminal Investigator
Criminal Investigator is a person who is charged with the duty of carrying on the objectives of criminal investigation The Primary Job of the Investigator: > is to discuss whether or not an offense has been committed under the law after determining the 5 W’s and 1 H. >By whom was it committed >Where was it committed? >When was it committed and under such circumstances >Why was it committed >Who committed it? >How was it committed?
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The Main objective of the Investigator:
is to gather all facts in order to: 1. Determine that a crime has been committed 2. Identify the victim and the offender 3. Locate and apprehend the accused 4. Presenting evidence of guilt
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The Qualities of a good investigator:
Perseverance with endurance Intelligence and wisdom of Solomon Honesty, integrity/incorruptible Understanding of the people and environment Keen power of observation and accurate description Knowledgeable about the laws on crimes, evidence, arrest, investigative concept/techniques, scientific aids, laboratory services, and about the criminals and their modus operandi, Keen power of observation and description Mastery in the oral and written communication The power to read between the lines
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Crime Scene Investigation
Crime Scene Investigation is categorized as Science, precisely Forensic science. Therefore, it follows methodical steps similar to any scientific research in order to arrive at a conclusion – which in this case is being able to identify the person responsible for the crime
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Basic Steps in Processing a crime scene:
(a). Securing the Scene: > The ability to preserve the crime scene in its natural state is one of the most important steps towards solving a crime. > If any changes were made to the crime scene, then the evidence you have gathered loses its authenticity. Hence, >You need to ensure that not only one aspect of the crime scene is preserved, but all areas are covered.
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(b) Examining the Scene:
*** As a rule, do not touch, alter or remove anything at the crime scene until the evidence has been processed thru notes, sketches, and photographes with proper measurements. > Proper documentation of the scene involves: (b.1) Photographing (From general to specific) - Taking photographs of the crime scene should begin the very minute you arrive. This will enable you to document every step of the crime scene investigation. All entry points toward the crime scene must also be photographed. Focusing on entry points provide investigators an idea on how one can have access to the crime scene. - The body of the deceased victim (if there is any) should not be covered until thorough processed for evidence.
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(b.2) Sketching Your first step before going about searching the scene for evidence is to create a sketch. If there are any physical features of importance to the crime, include them in the sketch. This will help assess the geographical location of the crime and other physical factors that could come into play.
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(b.3) Notes taking /Recording
> The investigator begins the process of recording pertinent facts and details of the investigation the moment he arrives at the crime scene. Create detailed notes of every bit of information you gather such as: >What type of clothing is he or she wearing? > What condition is it on? > Are there any bruises or wounds on the body? ***These could all indicate whether any struggles went on before the victim was killed at the scene.
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© Interviews and Testimonies
Onlookers can prove to be an annoyance to the ongoing crime scene investigation. However, you can look around for possible testimonies that would help provide more clues to the crime. For instance: if anyone could possibly have spotted the criminal before escaping from the crime scene. If there are any, then you could ask them for physical descriptions of the criminal.
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(d) Analyzing and Interpreting Evidence
This is the most difficult step in crime scene investigation. It will gather together evidence, whether physical or photographic, and investigators will place them side by side with all the testimonies you have gathered along with any observation you have made while examining the crime scene. Each item of evidence must be evaluated in relation to all the evidence, individually and collectively. >Some evidence might be required for examination in the laboratory to get more in-depth analysis of the evidence (e.g. f/p) that will point to the identity of the criminal.
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How DNA Analysis is used to identify with accuracy the perpetrators of crime
Human tissues such as hair strands, bloodstain, saliva, and other body tissues are often left in the crime scene. By proper collection, preservation and examination through DNA test of such pieces of tissues, their owner can be identified. The Supreme Court, in a recent case has made a pronouncement on the admissibility of the DNA test result. Hair strands left by the kidnapper in cases of kidnapping, lairs, bloodstains in clothing associated with murder, saliva stains in cigarette butts, stamps, envelopes associated with extortion, may all be used to help identify the perpetrators.
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DNA: Biological Evidence
- Blood - Semen - Tissue - Bones and teeth - Hair - Fingernails - Saliva - Bites - Vaginal secretions - Insect evidence - Plant evidence
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“You can’t argue with science”:
Landmark Cases on the Admissibility and Probative Value of DNA Profiling as Evidence People vs. Vallejo, 382 SCRA 192 (2002) In re: Petition to take the 1999 Bar Exams, B.M. No. 984 (25 June 2002) People vs. Janson, 400 SCRA 584(2003) People vs. Yatar, 428 SCRA 504 (2004) In re: The Writ of Habeas Corpus for Reynaldo de Villa, 442 SCRA 706 (2004) Gan vs. Pondevida, 382 SCRA 357 (2004) Tecson vs. COMELEC, 424 SCRA 277 Herrera vs. Alba, 460 SCRA 197 (2005) Agustin vs. CA, 460 SCRA 315 (G.R. No , 15 June 2005)
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“You can’t argue with science”: Landmark Cases on the Admissibility and Probative Value of DNA Profiling as Evidence People vs. Vallejo, 382 SCRA 192 ( In re: Petition to take the 1999 Bar Exams, B.M. No. 984 (25 June 2002) People vs. Janson, 400 SCRA 584(2003) People vs. Yatar, 428 SCRA 504 (2004) In re: The Writ of Habeas Corpus for Reynaldo de Villa, SCRA 706 (2004) Gan vs. Pondevida, 382 SCRA 357 (2004) Tecson vs. COMELEC, 424 SCRA 277 Herrera vs. Alba, 460 SCRA 197 (2005) Agustin vs. CA, 460 SCRA 315 (G.R. No , 15 June 2005)
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Supreme Court of the Philippines in People vs. Vallejo (G. R. No
Supreme Court of the Philippines in People vs. Vallejo (G.R. No , 09 May 2002) In this, the Court admitted DNA analysis as part of circumstantial evidence in affirming the death penalty of the accused for the rape-slay of a nine-year old girl. The DNA profile of the vaginal swabs taken from the victim matched the DNA profile of the accused.
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CAN YOU FORCE A PERSON TO SUBMIT HIS DNA SAMPLE TO SERVE AS STANDARD DNA IN A CRIMINAL OR PATERNITY CASE?
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People vs. Umanito, G.R. No. 172607 (October 26, 2007)
The Court acknowledges that “the determination of whether Umanito is the father of the AAA’s child, which may be accomplished through DNA testing, is material to the fair and correct adjudication of this case. Under Section 4 of the New Rule on DNA Evidence, the courts are authorized, after due hearing and notice, motu proprio to order a DNA testing, or on application of any person who has a legal interest in the matter in litigation.”
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Kirk Noble Bloodsworth 1st Death Row Inmate Exonerated by DNA
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Bloodsworth was convicted in 1985 of sexual assault, rape, and first-degree premeditated murder for the 1984 rape and murder of a nine-year-old girl in Rosedale, Maryland. Even though five eyewitnesses said that they saw him with the victim at the crime scene, he continued to maintain his innocence throughout his trial and subsequent incarceration. In 1992, while in jail, Bloodsworth read an account of how DNA fingerprinting had led to the conviction of Colin Pitchfork in the killings of Dawn Ashworth and Lynda Mann in Leicestershire, UK.
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Mr Bloodsworth says that while reading the book he had his own "eureka" moment. He realized that he could use DNA fingerprint evidence in his case, and that if it could be used to convict someone, it could be used to free them, too. Hoping to prove his innocence, he pushed to have the evidence against him tested by the then-novel method. Initially, the available evidence in the case — traces of semen in the victim's underwear — was thought to have been destroyed; however, when eventually located, testing proved that the semen did not match Bloodsworth's DNA profile.
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In 1993, Bloodsworth was released from prison and paid compensation, but he was not formally exonerated; by that time, he had spent almost nine years in prison, two of them on death row. It was this, he said, that inspired him to track down the real killer. In 2003, nearly a decade after Bloodsworth's conviction, prisoner DNA evidence added to state and federal databases identified the real killer, Kimberly Shay Ruffner.
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"I don't want the fact that I was the first person to be freed because of DNA testing to be my only legacy in life," Mr Bloodsworth explained. "I want it to be that I showed the world, I showed the US, that if it happened to me, it could happen to you. "I know there's more mistakes out there and none of us should ever sentence an innocent man to death or prison."
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How to safeguard the integrity of Physical Evidence
> The article/s should be properly identified > Continuity or chain of custody must be proved > Competency must be proved that the evidence is material and relevant.
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CHAIN OF CUSTODY/CHAIN OF POSSESSION
Chain of custody/Chain of possession – the number of persons who handled, transferred, and accounted evidence between the time of the commission of the alleged offense or between the time of its discovery and the ultimate disposition of the case.
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People vs. Vallejo (G.R. No. 144656, 09 May 2002)
In assessing the probative value of DNA evidence, therefore, courts should consider, among other things the ff data: The chain of custody How the samples were collected How they were handled The possibility of contamination of the samples The DNA testing methodology The procedure followed in analyzing the samples Compliance with the scientifically valid standards in conducting the tests
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COURT TESTIMONY As witnesses, law enforcement officers must ensure that the facts they present communicate the complete story and that their delivery of those facts makes their testimony clear and credible. Hence, “ The best method for having good and credible testimony is to follow best practices in your work”.
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THANK YOU AND HAVE A NICE DAY!!
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