Many serial killers display at least one trait of the McDonald triad, what are these traits
-Bedwetting past age of 10
-Animal abuse
-History of arson
How does the FBI classify serial killers
Organized and disorganized
Most common serial murder traits
Males who are prompted by sexual or aggressive drives to exert power through killing
What do successful investigations often depend on
Information provided by victims and witnesses and it typically taken by the first officer responding to the crime scene
What are the immediate concerns at a death scene
-Preserving the crime scene
-Identifying suspects and witnesses
What does a crime scene sketch accurately portray
-Physical facts
-Relates to the sequence of events at the crime scene
-establishes the precise location and relationship of objects and evidence at crime scene
An effective report is...
Concise, legible and accurate
Once a report is written...
The writer should proofread it
The most important step in report writing is...
To gather the facts
The 4th amendment to the US constitution...
Forbids unreasonable searches and seizures
A search conducted with a warrant must be limited to...
Only the specific area and items named in the warrant
The term criminalistics refers to...
The scientific study and evaluation of physical evidence in the commission of crimes
Securing the crime scene is a major responsibility of who?
The first officer(s) on the scene
modus operandi is pertains to...
The characteristic way a criminal commits a specific type of crime
Consent to search is only valid if...
Given voluntarily
When evidence is collected, an officer should record in their notes...
-time/date/location the item was found
-individual who found it
-case number
-description of item
-who took it into custody
What do latent prints consist of
Impressions of the ridges of the fingers transferred to other surfaces by sweat on the ridges of the fingers or because the fingers carry residue of oil, blood, dirt, or other substances
fingerprints cannot indicate what?
Age, race or gender
DNA profiling can be done using...
Cells from almost any part of the body
Footprints can indicate whether a person is...
Running, lost or carrying something heavy
Two basic requirements for obtaining information are...
Listen and observe
The most important rule to eradicate fear of testifying in court is...
To always tell the truth
Ballistics deal with...
The motion of a bullet
The most positive forms of identifying a person are through...
Fingerprint analysis and/or DNA
Latent prints are...
Those created by the natural oils on one's hands and left at the crime scene
Who should you interview first
Victim or complainant first
What is not accepted by the court as evidence
Polygraph results
What must a confession be to be valid in court?
voluntary
what is field or show-up identification
on-the-scene identification of a suspect by a victim or witness of a crime and must be close in time to the incident
What needs to be established before an arrest is made
probable cause
When are wiretaps legal
when there is probable cause and they are authorized by a court
what is homicide
the killing of one person by another
when is rigor mortis at its maximum
12-18 hours after death
what are common in knife attacks
defensive wounds on a victim's hands and arms
what offers valuable clues about time a body was left or buried
insects
elder abuse is...
severely underrepported
what is a predictor of abuse or violent behavior
cruelty towards animals
sex offenses include crimes such as:
incest, bigamy and child molestation
sexual penetration refers to...
in intrusion into a victim's anal opening, genital opening and mouth
a pedophile is...
the most common habitual child sex abuser
the basic purpose of crime scene photography is to...
record the entire crime scene permanently
The purpose of a marker in a photograph is to...
show the object's actual size relevant to the marker
being concise means to...
eliminate words
physical evidence at the scene of a robbery might include...
fingerprints, shoe prints and restraining devices
who should investigators partner with to search for stolen goods?
legitimate business such as pawnshops, second hand stores and flea markets
important evidence at the scene of a burglary is...
- safe insulation
- tool marks
- fingerprints
- footprints
- video surveillance footage
- paint chips
what is important in burglary investigations
DNA
what is "phishing
a method of tricking someone into voluntarily providing personal information about someone so that the information can be used illegally
ultraviolet light is good for finding...
trace evidence such as semen or fibers
AFIS
Automatic Fingerprint Identification System
Integrity of evidence refers to...
the requirement that any item introduced in court must be in the same condition as when it was found at the crime scene. This is documented by the chain of evidence, and is also referred to as the Chain of custody
What is the ultimate goal of interviewing and interrogating?
to identify those responsible for a crime and eliminate the innocent from suspicion
At the scene of a homicide a photographer should take photographs of...
- the room where the body is found
- the body from 5 angles
- close-up of the body wounds
- evidence of a struggle
photographs at the scene of a burglary should consist of...
- the exterior of the building
- point of entry
- crime scene entrance
- area from which valuable articles were removed
what is rigor mortis?
the stiffening of the joints due to enzyme breakdown after death
A signature in a serial killing is best defined as...
behavioral patterns of the suspect during the commission of the crime
who investigates terrorist o extremist bombing activity
Bureau of Alcohol, Tobacco and Firearms (ATF)
When collecting collecting gunshot residue evidence, an investigator should not
- handcuff the suspect
- fingerprint the suspect
- wipe/wash their hands
Transfer of evidence is...
evidence that has been transferred from one object or person to another object or person
what are riflings
spiral grooves cut into the barrel of a gun during its manufacture
what are 3 methods of discovering latent prints
- dusting powder
- super glue fuming
- spraying with Ninhydrin
where may physical evidence be utilized in forensic investigations
- courtroom testimony
- providing investigative leads for a case
- linking a crime scene or victim to a suspect
what does not change from birth to death and used by law enforcement to identify individuals
fingerprints
what are the 3 different fingerprint patterns
- loops
- whorls
- arches
what can compromise physical evidence
- heat
- humidity
- snow
- rain
- unnecessary personnel at a crime scene and/or spectators
once a latent print is developed it should be...
photographed and lifted
physical evidence collected at a crime scene must be...
admissible and credible
all states have laws requiring sex offenders to...
register within their states to help law enforcement agencies manage offenders released from secure confinement
What should you carry in your evidence collection kit?
- tweezers
- measuring tape
- paper bags in a variety of sizes
- magnifying glass
- phillips/flat head screw drivers
- hammer
- drug test kit
- latex gloves
- casting materials
why was serial murderer Richard Ramirez (Night Stalker) arrested
partially because of footprint evidence left at the scene of several murders
Why should you cast footwear impressions or tire tread impressions
because a cast provides a mold from which the actual size of the original impression can be determined, a cast can be used as backups to photographs and the depth of the impressions can be accurately measured via casting
A suspect's modus operandi can assist in their
- identification
- apprehension
- repression
- can be used to determine links between crimes
What is Locard's Theory
the theory that states that when two objects come in contact, evidence is transferred
how is a microscope generally used?
to determine whether or not a specimen is hair
what is the difference between a fully automatic weapon and a semi-automatic weapon?
Automatic weapons continue to fire as long as the trigger is depressed and the the magazine has not run out of ammunition
before collecting firearm evidence, one should...
take photographs of the firearm, making sure to include the
- serial number and model
- manufacturer's name and caliber
- safety on or off
- loaded or unloaded
Rifling is the process of...
putting spiral grooves on the inner surface of the barrel
what is the diameter of a guns barrel called
the guns caliber
to retrieve fibers an investigator can use...
tweezers, tape or a vacuum
what are the duties of a medical examiner?
- testify in court as an expert witness
- determine the cause and manner of death
- review medical history of deceased
the purpose of an autopsy is to
document any natural disease processes that have contributed to the death of the individual and document any injuries that have contributed to the death of the individual
what is the incision shape in an autopsy
Y
where is bile drawn from
the gall bladder
what is a good indicator of time of death
ocular fluid found around the eye
a Latin term that means stiffening of the joints of the body after death
Rigor Mortis
Most items of evidence will be collected in...
paper containers such as packets, envelopes, and bags
The two most common sources of DNA evidence are
blood and semen
the chain of custody refers to being able to...
account for an item of evidence from the time of its finding to its presentation of court
Quadrant or zone crime scene search patterns work best for...
a large outdoor crime scene
Corpus Deliciti refers to...
evidence which establishes that a crime has been committed
what is the professional name for an employee in a forensic laboratory who conducts scientific examinations
Criminalist
CODIS
(Combined DNA Index System) a linked national database of DNA samples from individuals convicted of sexual assaults and homicide
photo lineups include a minimum of how many pictures
6
an exemplar is an example of...
a suspect's handwriting
what can play a pivotal role in discovering the true identity of a perpetrator
the crime laboratory
the best definition of "Forensic Science" is
any aspect of science as it relates to the law
who created a system of anthropocentric measurements used to identify people
Alphonse Bertillon