Civil vs. Criminal Law CIVIL LAWCRIMINAL LAW filed by a private party. o a corporation o an individual person Penalty: a guilty defendant pays the plaintiff for losses caused by their actions. o no incarceration filed by the government Penalty: a guilty defendant is punished by o incarceration (in jail/prison) o fine paid to the government o execution (death penalty) Crimes are divided into 2 classes: o misdemeanors - less than 1 year incarceration o felonies - sentence of 1+ year
Direct Evidence = Eyewitness Testimony ◦ “I saw her do it!” “I heard him say it!” ◦ Eyewitness testimony is nonphysical evidence. Indirect Evidence = Physical Evidence ◦ “The victim’s hair was found on the defendant’s clothing.” ◦ “The defendant’s DNA was found at the crime scene.” Evidence generated by criminal activity is real evidence.
Pros: ◦ Easy to understand ◦ It appeals to our common sense Cons: ◦ Witnesses can be wrong ◦ Witnesses can lie ◦ Witnesses can be biased
Cons: ◦ Science (and scientists) can be hard for juries (and even judges) to understand ◦ If evidence isn’t collected or tested properly, the conclusions drawn from it can be wrong ◦ If there is some evidence that isn’t collected or some test that isn’t performed, then the conclusions drawn from what was collected can be wrong
PRO: Physical Evidence can be analyzed scientifically ◦ Science is not biased ◦ Science is logical, not emotional ◦ Science is repeatable and can be demonstrated to work again and again ◦ Conclusions drawn from good science can be trusted
Identification: ◦ Attempts to determine the identity of the evidence (especially if unknown evidence) to as high a degree of certainty as possible Examples: What did this hair come from? When the fire spread, was the accelerant kerosene or gasoline? Is this a blood stain? What is this unknown fiber
Comparison: ◦ Determines if two objects (the evidence and a standard) have a common origin (are made of the same materials, come from the same factory, were both at the crime scene, were both fired from the same weapon, etc)
Evidence that is not unique Not used to identify a person An examiner can only figure out if the evidence being analyzed belongs to a particular group ◦ Examples: Blood Type Car Make and Model Hair Color Clothing fibers Soils Illegal drugs
Evidence that connects to a specific individual Unique The evidence identifies the individual. This piece of evidence can’t be linked to anyone else. ◦ Examples: DNA Custom Paint on a Car Fingerprints
ORGANIZATION of a CRIME LABORATORY
Drugs ◦ Identify the type of drugs Glass ◦ Particles being transferred from suspect to the crime scene or the crime scene to the suspect. ◦ Glass containing bullet holes or other projectiles Explosives ◦ Identifies the explosive ◦ Examines the charred remains of the explosion.
Impressions ◦ Markings from: Tires Shoes Fabric Teeth Petroleum products ◦ Accelerants in arson ◦ Grease, oils found at the crime scene
Plastic bags ◦ Associated with homicides and drug cases ◦ Identified with similar bags in the possession of a suspect. Plastics, rubbers and other polymers ◦ composition may be unique to a manufacturer. Powder residue ◦ Indicates firearm use.
Soil and Minerals ◦ link a person to a location Vehicle lights ◦ Lights at accidents are checked to see if they were being used Fingerprints ◦ Examination of visible, latent or plastic prints. Serial Numbers ◦ Identifies stolen property ◦ Filed down or altered numbers can be recovered
Blood, Semen, Saliva: ◦ Identifies individuals who may have been present at a crime scene. Wood and vegetative matter ◦ Wood, sawdust, shaving, leaves, flowers can link a person to an area. Fibers ◦ Natural or synthetic fibers that are transferred at the crime scene.
Firearms & ammunition ◦ Weapons ◦ Ammunition ◦ Casings ◦ Bullet holes Tool Marks ◦ scrapes and scratches on a surface will match the tool that made it.
Documents: ◦ Handwriting and typing ◦ checks for authenticity of author ◦ Inks and paper ◦ checks for composition and age. ◦ Related items, charred, burned or altered documents.
Organs & Physiological fluids ◦ Detects drugs and poisons ◦ Metabolic disorders
Evidence Collection
Cross contamination with another vehicle or person can transfer the following: ◦ tissues ◦ blood ◦ hair ◦ soil ◦ paint ◦ broken glass ◦ fabric impressions Evidence is located by: ◦ Vacuums ◦ Scraping ◦ Visual examination of the area
Evidence from the Scene: ◦ Broken glass ◦ Blood ◦ Weapons ◦ Rope, tape ◦ Victims clothing ◦ Fingernail scrapings ◦ Head and pubic hairs ◦ Blood ◦ Vaginal, anal and oral swabs ◦ Recovered bullets
Each item must be packaged separately ◦ Plastic pill bottles are useful for: Hairs Glass Fibers Other types of trace or small evidence ◦ Manilla envelopes, glass vial or pill boxes are also useful ◦ Specialized Containers are required for: Bloody Clothes: Need to be placed in paper bags. Arson Residue: Glass or metals containers with sealed lids.