Investigation of the Violent Crime Exemplar

Cause of Death and Odds of Occurrence Disease Heart Attack Cancer Auto Accident Suicide Homicide 1 in in 3 1 in 5 1 in 42 1 in 81 1 in 84

Homicide Investigation There are about 25,000 homicides a year. Some years up to 65% of homicides are solved by the arrest of the perpetrator.

LAW of Homicide 1 st Degree: (cold-blooded murder) proof of premeditation, deliberation, & malice. (planning, coolness, scheming) 2 nd Degree: (hot-blooded murder) proof of malice aforethought & intent to do bodily harm. Voluntary Manslaughter: (heat of passion) proof of provocation & no time to cool off. (self- defense is common defense) Involuntary Manslaughter: (accidents) reckless disregard of the consequences. (insanity)

ADAPT Assess Scene Detain Witnesses Arrest Perpetrator Protect the Scene Take Notes

Estimating Time of Death Body Temperature: –Bodies cool down after death. –The temp drops from 98.6 by a factor of 3 degrees in the first hour and a factor of 1 degree each subsequent hour. –After 30 hours, decomposition causes the temp to rise. –See chart in Lecture 1 Packet.

Estimating Time of Death Rigor Mortis –The body is limp until 6 hours after death. –Hardness begins around jaw area and spreads through body. –By 36 hours after death the body is limp again.

Estimating Time of Death Lividity –The effect of gravity on the body –After death all of the loose blood in the body runs down to the lowest point of gravity. –Causes bluish-purple stains. –Begins after 3 hours and blood is dried by 12 hours.

Estimating Time of Death Eyes –Eyes dilate 7 hours after death. –After 12 hours, the eye becomes cloudy.

Estimating Time of Death Food – Anything undigested was eaten in last 2 hours. –Food spends 6 hours in small intestines and 12 hours in large intestines.

Estimating Time of Death Underwater Victims –Average dead person sinks for 8-10 days. (depending on weight) –On or about day 11, bodies will begin to float.

Estimating Time of Death Decomposition & Entomology –Decomposition begins after 30 hours –Over time it causes a bloated greenish tint. –Blowflies – Green Bottle Flies lay eggs on dead bodies which become maggots. –Measure largest maggot in mm + 2 = approximate # of days since death.

Greem Bottle Fly – AKA: Bowfly

Sexual Assaults Any victim of sexual assault should be examined by: –SART: sexual assault response team. –SANE: sexual assault nurse examiner.

Sexual Assaults Evidence may include: DNA, fingerprints, hairs, fibers, & blood. “The logical solution to a rape case involves matching trace evidence from three places: the crime scene, the victim and the perpetrator.”

Sexual Assaults Most forcible rapists claim to be a victim of mistaken identity… they claim they are not the perpetrator. Once evidence identifies them, they claim it was consensual sex.

Sexual Assaults Some rapists use drugs to erase the memory of their victims. –Gamma-hydroxybutyric (GHB) –Rohypnol –Ecstasy Victim is often unaware of crime until it is too late for most examinations to be helpful.

Sexual Assaults Last type of sexual offender targets children Offenders may be someone the victim knows. Many children are reached via the internet.

Motive, Means & Opportunity Motive: Purpose, reason, grounds. Means: Who has the physical strength to commit this particular crime. Opportunity: who had access to or could have been present at the crime scene.