CHAPTER 2: CRIME SCENE II-1 WHAT IS CRIME SCENE? • Place where the crime occur and most of the evidence can be collected there. After process of identify and recorded finished, the evidence must be collect, preserved, packaged and inventoried. 1. COLLECTION OF EVIDENCE • Gloves must always be worn and changed to avoid CONTAMINATION. • FLASHLIGHT or ALS (alternate light source/ fluorenscense light) help to identify the evidence. TYPES OF EVIDENCE 1. HOW TO MANAGE TYPES OF EVIDENCE IMPRESSION EVIDENCE (FINGERPRINT, SHOE PRINT) BIOLOGICAL EVIDENCE (BLOOD, SEMEN) FIREARMS AND AMMUNITIONS (GUN, BULLET) ARSON EVIDENCE (FLAMMABLE SOLUTION) CHEMICAL & CONTROLLED SUBSTANCES (DRUGS) • Identified using sight such as flashlight or chemical reagent. • collected using lifting tape or molding material. • photograph and chemical developers. • Identified using sight, ALS or chemical reagent. • Collected using the sterile swab. • Must be safe. • stored in box. • locate by sight and smell. • Stored in can since it is easily evaporate. • Stored in vial or glass container. * ARSON EVIDENCE must be tested using GC-MS since it is evaporated easily. I WHAT IS THE GOALS FOR EVIDENCE PACKAGING? HEALTH SAFETY • biohazards • Sharp tools • Accidental firearm discharge PROTECT EVIDENCE • Loss • Contamination • Cross transfer • Damage CORRECTLY IDENTIFY EVIDENCE • evidence description • Evidence source • Chain of custody 2. PACKAGING EVIDENCE • Should indicates (types of process needed, health hazard and storage condition). • each evidence must be placed SEPARATELY to avoid CONTAMINATION. • The packaging must be clearly sealed and sealed with evidence tape. • wet biological evidence must be air dry before pack. CARDBOARD BOXES • To store heavy and bulky evidence such as WEAPONS, KNIVES & LONG GUNS. • Small boxes to store BULLET, CARTRIDGES and others. PLASTICS • ADVANTAGES: strength for it weight and transparency to allow inspection. • DISADVANTAGES: water vapour cannot easily passes through it. • Will make metals rust. GLASS VIALS & JARS • useful for liquid samples • (blood, alcohol, flammable liquids and water) METAL CANS • To store NON-BIOLOGICAL EVIDENCE THAT NON-EVAPORATE. • EXAMPLE OF flammable liquid accelerants ( gasoline, charcoal lighter fuel). * don’t use plastic because it allows hydrocarbon vapours to escape. WHAT HAPPEN WHEN BIOLOGICAL EVIDENCE IS WET? • Evidence will ‘leak’ throughout the exterior of the packaging. • So the evidence will: damage, loss and contaminate. ELEMENT OF PACKAGING EVIDENCE/ TYPES OF PACKAGING PAPER • • • • porous - allowed water vapour to escape. To store clothing and cloth for DNA test. To store plant materials such as marijuana. when store in PLASTIC all this samples will mold and decompose. SOMETIMES PACKAGING ALSO NEED INTERNAL PACKAGING: • • • • • BINDLE COIN ENVELOPE BOX HOLD DOWN DEVICE SYRINGE TUBE 3. SEALING EVIDENCE 4. SUBMITTING THE EVIDENCE TO THE LAB TYPE OF SEALING • Must directly submitted to the lab. • CHAIN OF CUSTODY • once at lab, the evidence is placed in secure storage areas and logged as to location. • Heat seal • Tape seal • Lock seal HOW TO CORRECTLY SEAL THE TAPE? CHAIN OF CUSTODY Tape seal across the entire envelope’s flap Including initial and date. WRONG WAY TO SEAL THE EVIDENCE • To record the movement of the evidence. • Investigator must documents everything that happen to the evidence from the crime scene until in the lab. CHAPTER 6 FIREARMS & TOOL MARKS BALLISTIC - the movement of projectile in the firearm. FIREARMS IDENTIFICATION LIST OF ANALYSIS BULLET COMPARISON • The gun barrel is drilled/hollowed out, so it will leave mark at the barrel’s inner surface. • the bullet also containing it own shape. • Pulling the trigger release the firing pin. • The firing pin will strikes the primer. • The primer ignites the gun powder. • The powder release gas that propels the bullet for ward through the barrel & eject the cartridge. WHAT TO DO? • • • • CALIBER- the diameter of the gun barrel. Bullet comparison Weapon function Gunpowder Residue Detection Muzzle-to-target distance • LANDS - is the surface bet ween the grooves. • This is known as rifling. • As the bullet spinning passing through the barrel, it will be marked by the grooves. CLASS CHARACTERISTICS! EXAMPLE: • .32 caliber Smith & Wesson - 5 land & grooves to the right • .32 caliber Colt - 6 lands & grooves to the left Can also be INDIVIDUALS CHARACTERISTICS if there are IMPERFECTIONS! THE TESTS FOR BULLETS 1. Bullets must be fired through the suspected barrel. ( to match bullet and gun) 2. GODDARD & COMPARISON MICROSCOPE ( to match the mark on the bullet). 3. CARTRIDGE MARKING ( impression/mark on the cartridge). Caliber is recorded in • hundredths of an inch (.22 and .38) • Milimeter (9mm) BULLET ANATOMY Marks on the primer. WHY DIFFICULT TO GET PERFECT MATCH? • Rust at the barrel • The bullet is too damaged due to the impact • Microgrooves (8-24 grooves) CARTRIDGE - is the outer case of the bullet SHOTGUNS • The barrel is smooth (the projectile not marked as it passes through) • Fire small lead balls or pallets. • GAUGE - Diameter of the barrel. GUNSHOT RESIDUE (GSR) • Containing lead (Pb), barium (Ba) and antimony (Sb) THE TEST FOR GUNSHOT RESIDUE 1. GRIEF TEST - to detect the presence of nitrates. (By swabbing the suspect’s hands) (for distance determination). NEGATIVE RESULT DUE TO: • Washing the hands. • Wearing gloves. • Lead free ammunition. SERIAL NUMBER RESTORATION • INDIVIDUAL CHARACTERISTICS. • Use acid solution to clear the metal. FIREARMS RESIDUE COLLECTIONS • • • • • • Make sure it is unloaded. Do not put anything in the barrel. Check the magazines. Place ID tag at the trigger guard. Wrap in tissue to protect. Place in pill box or envelope. CLOTHING RESIDUE COLLECTIONS • Air dry/ room temperature if wet. • Put in paper bags. • Package separately. CHAPTER 5: GLASS EVIDENCE DEFINITION OF GLASS Inorganic production of fusion that has been cooled to a rigid condition without crystallization. HOW TO PRODUCE GLASS • Melt the sand (silica) and the ash (Na2CO3). • Ash function as flux to decrease the melting point. • Lime (CaO) functioned to make the glass water-insoluble. • Oxide added are varies. • Boron was added to increase the temperature stability, so the glass will resistance to high temperature. • Lead was added to increase the density so the glass will sparkle as the crystal. SUBMERSION METHOD • The lower the number, the higher the refractive index. • If the glass cannot be seen in the solvent, so the RI for the glass is the same with the RI of the solvent. • The piece of glass was immersed in the solvent. BECKE LINE • Investigated using a low power compound microscope. • If the line inside the parameter of the glass, the RI of the glass is higher than the solvent. • If the line outside the parameter of the glass, the RI of the glass is lower than the solvent. NATURE OF GLASS • Brittle • Transparent • Amorphous • Conchoidal fracture GLASS COLOUR • The original colour is green due to the iron oxide. • Manganese clean the colour, but if too much it turn into purple. • Iron and Sulphur turn the glass into brown. • Green - chromium. • Red - gold or copper dust. • Yellow - silver. • White - tin. GLASS PROPERTIES -DENSITY • D= m/V • Mass can be determined using the balance. • Volume determined using water displacement process. • Fill a beaker with water. • Place a graduated cylinder at the mouth of the beaker. • Place the piece of glass in the beaker and collect the overflowed water. • That is the volume and use the formula to determine the density. -REFRACTIVE INDEX • The changes of light’s direction when the speed change. • When light pass through a less dense material to a denser material, the light will reflect to the normal line. • Increase density, decrease speed. WATER DISPLACEMENT FOR DENSITY DETERMINATION AUTOMATED RI INDEX MEASUREMENT ' • Using GRIM 2 (Glass Refractive Index Measurement) CHAPTER 7 : DRUGS & TOXICOLOGY • DRUGS - Any substances that produces physiological or psychological change within a short time after an easy dose of ingestion. • DRUGS DEPENDENCE - a situation when someone have a very strong attachment with the drugs. DEPENDENCE PHYSIOLOGICAL • A need by the body to prevent sickness such as cancer. PSYCHOLOGICAL • Uncontrollable “craving” • Desperate to continue. STIMULANTS • To feel more energetic, strong or awake. PRODUCTS/ ACTIVE INGREDIENTS: AMPHETAMINE/ METHAMPETHAMINE - Produced in clandestine lab COCAINE - A very powerful stimulant - Causing enormously psychological dependance. COCAINE HYDROCHLORIDE • Inhaled through nose. * ‘crack’ vaporised by heat and inhaled into the lungs. DRUGS & SOCIETY (CONTROLLED SUBSTANCES) • Federal Controlled Substance Act • State Act Methamphetamine TYPES OF DRUGS • • • • Narcotic drugs - to dull the pain (analgesic) Stimulants - to increase the mental & physical energy Hallucinogens - to change the mental state Depressants, Hypnotics & Tranquillisers - to dull one sense, to reduce anxiety • Club drugs- to increase one’s enjoyment in party • Performance Enhancing Drugs - to build muscle NARCOTIC DRUGS/ OPIATES: • Also known as PAINKILLERS • OPIATES: natural drugs derive from the opium. • Causing severe psychological symptoms. • SOURCES: POPPY PLANT • Dried sap of the opium poppy plant • Can be smoked directly or processed to isolate the morphine • PRODUCTS/ ACTIVE INGREDIENTS: MORPHINE • Primary active drugs. CODEINE • Secondary active drugs. HEROIN • Derivative from MORPHINE. * when you take heroin and peed, it will change to MORPHINE. HALLUCINOGENS • Causing hallucination. (Altered the mental state) • SOURCES: MARIJUANA & HASHISH (another form of marijuana from the flowering top of plants) PRODUCTS/ ACTIVE INGREDIENTS: CANNABINOIDS (Active ingredients) • eg: THC • When pee the THC will turn to carboxylic acid. LSD • extremely potent hallucinogen. • 30-50 micrograms only. PCP (angel dust) • simple to make. • Made in clandestine lab. SOURCE: PEYOTE • the bud of particular cactus • ACTIVE INGREDIENTS: MESCALINE SOURCE: MAGIC MUSHROOMS • genus Psilocybe. • ACTIVE COMPONENTS: (PSILOCIN & PSILOCYBIN) DEPRESSANTS, HYPNOTICS & TRANQUILLISERS - PRODUCTS/ ACTIVE INGREDIENTS ALCOHOL BARBITURATE VALIUM (relieve anxiety) ROHYPNOL CLUB DRUGS PRODUCTS/ ACTIVE INGREDIENTS MDMA/ LOVE DRUG/ ECSTASY - Made in clandestine lab or imported legally from other countries. GHB (gamma hydroxybutyrate) - related to GBL - Used for hypnotic or depressant effect KETAMINE - Animal tranqulizer - causing amnesia and lost of memory. ANALYSIS / DRUGS TEST 1. SCREENING TEST • A small amount of drugs was placed in a pouch. • the sealed ampoule is then broken to release the solvent. • The colour changes is recorded. * However, screening test is not substitute for laboratory test. OTHER SCREENING TEST • • • • SCOTT TEST - COCAINE DUQUENOIS- LEVINE TEST - MARIJUANA (navy blue) MARQUIS TEST - OPIATES (purple) VAN ERK TEST - HALLUCINOGENIC DRUGS 2. ISOLATION & SEPARATION • Include initial microscopic examination - to determine number of materials that present. • PURIFICATION STEP - To separate the controlled materials from the substance. • LIQUID-LIQUID EXTRACTION/ CHROMATOGRAPHY- to separate the materials. 3. MICRO CRYSTAL TEST - To examine the morphology of the drugs. • this test is rapid and specific. • only small amount of sample needed and placed on the microscope slide. • Then, reagent was added. 4. CHROMATOGRAPHY ATHLETIC PERFORMANCE DRUG PRODUCT/ ACTIVE INGREDIENTS ANABOLIC STEROID • Promotes cell growth of muscle tissue and sometime bone size and strength • Separate mixture of different compound. • Moving phase & Stationary phase. • Based on retention time and distance traveled. 5. SPECTROSCOPY/ SPECTROMETER • Interaction of electro-magnetic radiation to give spectrum. • used: mass spectrometer (MS) or Infrared spectrometer (IR) • GC-MS & GC-IR • LC - MS (provides a retention time along with a spectrum for unambiguous identification. FORENSIC TOXICOLOGY (ANTEMORTEM & POSTMORTEM) ANTEMORTEM - Living individuals - eg: urine POSTMORTEM - Deceased / died CLASSES OF POISON • INORGANIC (arsenic, cadmium, cyanide) • ORGANIC ( strychnine, curare, digitalis) • BIOLOGICAL (venom, botulism, tetrodotoxin- ubat kulat) DRIVING WHILE IMPAIRED ALCOHOL • 8% w/v • 80 mg ethanol / 100 ml blood • TESTED USING: BREATHALYSER & INTOXILIZER INSTRUMENT CHAPTER 10: FINGERPRINT EVIDENCE WHAT IS FINGERPRINT? WHORL 35% of the population • The reproduction of friction ridges on the tips of fingers and thumbs. • The scientific study is called DACTYLOSCOPY. • Ridges are form before the baby was born and maintain their pattern throughout the life. TYPES OF FINGERPRINT PLASTIC FINGERPRINT • Visible • Occur when the finger touch soft surfaces. LATENT/ HIDDEN FINGERPRINT • The oil, sweat or amino acid that left on surface touched. PATENT/ VISIBLE FINGERPRINT CHARACTERISTIC OF FINGERPRINT • • • • ARCH LOOP WHORL COMPOSITE ARCH Only 5% of the population LOOP 65% of the population BASIC & COMPOSITE RIDGE CHARACTERISTIC HOW TO IDENTIFY THE LATENT FINGERPRINTS? • Dusting • Chemically fixing DUSTING • Hard surfaces was dusted using colourful powder. (Based on the surface colour) • The powder can be brushed using camelhair or fiberglass brush. CHEMICAL FIXING SUPER GLUE FUMING/ CYANOACRYLATE (non-porous surface) • super glue is heated in enclosed area (using gallon plastic bag) • print appear in off white colour. • POLYMERISATION process occur. • the glue vapour attached to the ridge residue. • As harden the print being develop. SILVER NITRATE METHOD (porous surface) - most effective o paper. - silver nitrate has low toxicity. • spraying, dipping or brushing. • easy and fast. EOSIN TECHNIQUE • Develop print with pink appearance on white non-coloured paper. • Iodine attached to the calcium in the sweat. • ninhydrin react with amino acid in the sweat, moist heat is applied using steam iron or humidity chamber.
