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Introduction to Forensic Science Guided NotesName:_____________________Forensic ScienceForensic science is the ______________________________________________________________. Forensic science is a very broad discipline, encompassing bothCriminalistics – _______________________________________________________________________________Criminology - ________________________________________________________________________________ ___________________________________________________________________________________________Forensic Science CareersCrime Scene Investigators_______________________________________________________________________________ _______________________________________________________________________________.Some of the evidence may be analyzed by the CSI team that collected it, but much may be sent to laboratories or specialists. Most jobs require a ______________________________________________________________. Some, but not most, require that you be a sworn police officer.Pay is about $45k – $55 kCriminalist / Forensic Scientist_____________________________________________________________________________ _____________________________________________________________________________. Often specialize in just one or a few areas. Nearly all jobs require a __________________________________________________, and some require master’s or doctoral degrees Some experts may help police only occasionally and have another job (e.g. doctor, professor) Most forensic scientists make ~50k-65k, but the head of a lab or some in-demand specialists may make $75k-$100 kForensic Specialties_______________________Determines a person’s competency to stand trial, sign documents, or make medical decisions; determines motivation of suicide victims, and provides psychological profiles of suspects.________________________Gathers evidence from the body and/or living victims. Reviews medical records, witness statements, police reports, conducts autopsies, and determines cause of death. ____________________Examines plant fragments, pollen, or soil to place a suspect at a crime scene or to determine whether a body has been moved.____________________Determines the types of fluids present and matches samples of fluids to victims or suspects._____________________Examines and identifies firearms, bullets, and shell casing, and searches for gun shot residue.____________________Examines finger, palm, and foot prints, and matches them to prints taken from suspects, other crime scenes, or databases.____________________Examines marks found on the crime scene and matches them to tools found with suspects._____________________Uses insect larvae found in corpses to determine time of death and whether the body has been moved from one location to another____________________Determines the authenticity and authorship of various documents____________________Analyze and compare hair, fibers, glass, soils, and paints to determine their type and origin, and to place suspects at the crime scene ____________________Identifies unknown bodies by comparing teeth with dental records or matches a suspect’s teeth with bite marks on the victim or other evidence.____________________Collects, protects, and transports evidence from the crime scene to the crime lab. May also sketch and photograph the crime scene._____________________Examines skeletal remains to determine age, sex, and race of the deceased. May also identify types of injury / disease and establish time of death. Forensic PathologistsA physician with special training in pathology (disease)___________________________________________________________________________________ ___________________________________________________________________________________Other responsibilities:Reviews medical historyReviews witness statementsPerforms autopsyCollects evidence (toxicology, microscopic examination of organs, DNA analysis, etc.)Writes a report, include an official cause of deathProvides testimony in criminal courtIn complicated cases, a forensic pathologist may also be asked to examine and photograph the crime scene himself.Most salaries are between $75k-$140k, but can be as high as $400k, especially in private sectorMedical Examiners vs CoronersThe person _______________________________________ to perform autopsies and determine cause of death may be either a medical examiner or a coroner.Medical examiners ___________________________________forensic pathologistsCoroners __________________________________________ forensic pathologists, or they may be doctors with a different specialty (e.g. obstetrics), or they may not even have any medical training at all.Most counties have adopted the newer medical examiner system, but some rural areas still employ coroners.Expert witnesses and the lawIn any case involving a death, the _______________________________ will testify Experts in other specialties may also be called to testify It is the ________________ who decides ___________________________ to be considered an expert and ______________________ they are allowed to presentLegal precedent for expert witness testimonyFrye vs. United States (1923)“Frye Standard”: expert testimony must be based on “______________________________ scientific principle” that is “________________________________” and has obtained “__________________________” in the scientific community Daubert v. Merrell Dow Pharmaceutical, Inc. (1993) “Rule 702” or “Daubert standard”Explicitly states that it is up to ______________________________ whether to allow testimonyOffered judges the following guidelines for admissible techniques and theories subject to testing and _____________________________________________________known __________________________Attained widespread _______________________center0How do these two standards differ?00How do these two standards differ?Other rules for expert witness testimonyExpert witnesses are ______________________ before the jury What does this mean? Experts testify as to their ______________________, ___________________, and ____________________________ before presenting evidence.Because they must explain complicated information, expert witnesses have much greater freedom in how they testify (i.e. they can _______________________, rather than just _____________________ __________________________________)Types of Evidence – Direct vs. Indirect__________________________ - Evidence that establishes a fact ______________________________ ___________________________Example: _______________________________________________________________________________________________________ / circumstantial evidence - Evidence that only provides a ___________________________________ about a factExample: _____________________________________________________________________Direct or Indirect?Soil matching a crime location found on a suspect’s clothing Possession of an illegal substanceVideo of a person committing a crimeFingerprint at crime sceneFingerprints on the murder weapon DNA match to skin under victim’s fingernailsWhen could you argue that fingerprints on the murder weapon are direct evidence?When could you argue that fingerprints on the murder weapon are indirect evidence?What about skin under the victim’s fingernails? When is it direct? When is it indirect?Types of Evidence – Testimonial vs Documentary vs PhysicalTestimonial evidence -- _________________________________Documentary evidence - _________________________ relevant to a crime Example: audio / video / written documentsPhysical evidence -- any object or material relevant to a crimeWhich type of evidence?DVD stolen from a storeSurveillance video of a robberyCrime scene photographsProblems with eye-witness accountsMost cases of wrongful imprisonment are due to mistaken eyewitness identification!Eye witnesses may be wrong for many reasons:Age / eyesight / hearing / alcohol or drugsStress / fear can focus and alter perceptionsEncounters may be brief or take place under poor conditionsNew information may alter memories Physical EvidenceAlthough ________________________, physical evidence is more reliable than eyewitness accounts.With enough physical evidence, a strong case can be made. What can physical evidence show?It can ______________________________ at a the crime scene or with the victimIt can help _______________________________ (for example, blood splatter can indicate the relative position of two people)Can ___________________________________ / indicate that crime took place (e.g. finding gasoline at a fire indicates arson)Locard’s Exchange Principle:“___________________________________________________________”Every time someone goes somewhere, they leave behind physical evidence, and pick up trace evidence from their environment.Probative ValueThe more unique or _______________________________ a piece of evidence is, the better its _______________________________________ – the stronger proof it provides.Example 1:Finding that a suspect has the same brand of duct tape that was used in a crime is ok evidence.BUT, if the torn end of the duct tape used in a crime exactly matches the torn end of the suspect’s role, that is much better evidence.Example 2:A footprint is found at a crime scene. The size matches a suspect, but it’s a common size. How can the print be further individualized?Describing EvidenceDetermine whether each type of evidence listed below is direct or indirect, physical or testimonial. For physical evidence, also describe additional details that might individualize the evidence and/or increase its probative value. Survelliance camera videotape of a crimeWritten contractBlood stained clothingEyewitness accountHair found at the crime sceneCrime Scene Investigation ProcedureCrime scene _______________________________________________________________Primary crime scene _________________________________________________________Secondary crime scene _______________________________________________________First responders _____________________________________________________________Duties of the first responders_____________________________________Establish scene diametersIdentify potential hazardsAssist injured personsSearch for and arrest suspect, if possibleWhat is the importance of scene management?What is the drawback of first assisting injured persons?_______________________________________Use physical barriers like vehicles and/or crime scene tapeEstablish a crime scene security officerKeep a security log of all entries and exitsMay use multilevel securityWhat important principle of forensics is related to the need to secure the crime scene?What is the benefit of multi-level security?Duties of the crime scene investigator___________________________________________________________Review existing security and adjust if necessaryDetain, isolate, and interview witnesses and suspectsCoordinate team membersWhy must witnesses be isolated?____________________________________________________________________________________Identify transient evidence,Note all areas (such as exits and entrances) that need special attention, Assess the need for specialty equipment or personnel,Take initial photographs and documentationDocument the scene with photographs, videotapes, and/or sketches Collect and package evidence __________________________________________________________________________________________________________Why is chain of custody important?Crime Scene Evaluationleft7747000What was done correctly in Scenario A? What was done incorrectly, and how could it have negatively affected the investigation?What was done correctly in Scenario B? What was done incorrectly, and how could it have negatively affected the investigation?What was done correctly in Scenario C? What was done incorrectly, and how could it have negatively affected the investigation?Crime Scene Search PatternsInvestigators often use geometric search patterns while searching for evidence to ensure that no evidence is missed.left37168700The type of search pattern depends on the scene. SJot down some benefits and drawbacks of each search pattern.Take notes on the best use of each search pattern.Grid –Spiral – Parallel / Linear – Zone / Quadrant – Crime Scene Search Pattern Questions1) Investigators believe a body may have been dumped in a large field. What search pattern be used?SpiralGridParallelZone2) A very high profile crime has been committed, and the police has been given a lot of resources and manpower to solve it. Which pattern is appropriate?SpiralGridParallelZone3) Police have a warrant to search a suspect’s car. Which pattern is appropriate?SpiralGridParallelZoneCrime Scene NotesInvestigators take detailed notes on all of the following:Step-by-step description of every action taken by investigators.Date, time, location, weather, environmental conditionsDescription of crimeLocation of evidence with reference to other fixed pointsNames of all people on the scene, including authorized personnel, witnesses, victimsCrime Scene PhotosThe scene should be thoroughly photographed_______________ evidence collection.Types of photos: _________________________(exterior and interior)__________________________________________________Use scales and numbered placards with photosCrime Scene VideosCrime scenes should be videotaped starting outside and moving in, all around the crime scene. Important details (time, place, and objective descriptions should be included, other narration should be avoided. Should not include members of the investigative team.Crime Scene SketchesRough sketches are done on the scene, and finished, to-scale sketches are completed later.Crime scene sketches should be labeled with: A titleA legend with letters, etc., for key pieces of evidenceCompass directionScaleCase numberOffense type Location-10985521251400Example rough sketchCorresponding finished sketch31744864931800In order to record exactly where the evidence is located, each and every piece of evidence must be measured from at least ________________________________. This is called __________________________.In practice, this is often most easily done by recording the ______________________________ coordinates / distances of every piece of evidence in the room.Evidence CollectionOften, just one person designated as evidence collectorEnsures that evidence is collected, packaged, and marked in a consistent mannerResponsible that nothing is lost of contaminatedOften wears face mask, lab coat, gloves, shoe covers, eye protection … why?_________________________ collected firstEach piece of evidence is packaged separatelyMost pieces of evidence will go in two containers, each sealedOuter container will be labeled with: Name of collectorDate, time, and location of collectionType of evidence________________________________ (list of all people who came in contact with a piece of evidence)Controls are taken for comparison_________________________________________ – evidence with a known originExamples:If a blood stain is found, blood would be collected from victims and suspects for comparison.___________________________ are often done to collect DNA reference samples_______________________________________ – sample of surface material close to where evidence is foundExample:If arson is suspected, investigators will collect residue from an area believed to be exposed to an accelerant (e.g. gasoline) and also collect material from a nearby area not believed to be exposed to the accelerantEvidence PackagingDifferent containers are used for different types of evidence.________________________________________________ should be dried and stored in porous materials (cardboard, paper) to prevent moldEvidence from suspected __________________ should be stored in air-tight containers (such as tightly sealed jars) to prevent __________________________ from evaporatingPlastic pill bottles work great for small ____________________________________________________Powders are typically stored using a ‘_________________________________________’right570590WarrantsThe fourth amendment protects against ‘unreasonable search and seizure’Warrants are obtained from a __________________, after police has demonstrated ____________________________, usually through a written ______________________, but sometimes over the phone.Warrants have limited ________________________. If police go beyond the scope of the warrant that evidence is usually inadmissible in court. However, if evidence not included on the warrant is in ‘____________________________________’ during a search it is usually admissible in court.Police must _______________________________________ a warrant search. However, if no one answers or if they are denied entry then they may break down the door to conduct the search. Also, judges may give written permission for police to just break in under circumstances suspected to be dangerous.When are warrants not necessary?During emergency circumstancesIf necessary to prevent immediate destruction or loss of evidenceSearch of person or property under immediate control of someone who has been lawfully arrested“Stop & Frisk” – stopping and patting down someone reasonably suspected of a crimeSearches made by consent of party involvedIs a warrant necessary? Why or why not?Police want to obtain a blood sample from a person who has been arrested.Police come upon the scene of a homicide and search for the killer.Police come upon the scene of a homicide, located within an office building, and search for trace evidence.A store has just been robbed. Police stop and search the pockets of two teens loitering in the area.Police have a warrant to search for an ax believed to be used in a murder. They search the house thoroughly, finding a baggie of drugs in a sock drawer. Are the drugs admissible?Is the evidence admissible? Why or why not?Police pull over a person and ask for permission to search the car for a weapon. The person grants permission, and the police find a bag of drugs. Is the bag admissible in court?Police have a warrant to search a home for a murder weapon and find a bag of drugs on the kitchen counter top. Is the bag admissible in court?Knock and wait? Or not?Police obtained a call about a domestic disturbance. When they arrive, they hear screams from inside. Police have a warrant to search for drugs. They knock then hear the sound of a toilet flushing.Police have a warrant to search for a weapon. They knock, then hear the sound of a toilet flushing. ................
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