Investigations final exam

Criminal investigations

Activities conducted to collect evidence in order to achieve certain goals

Criminal Evidence

Also known as crime-related information; criminal evidence is collected during criminal investigations.

Forensic Science

field of science that addresses legal questions

Reactive Investigations

investigators receive info of criminal activity and there is urgent need to interfere

Case screening

process of selecting cases for a follow up investigation depending on the severity of the crime

Solvability factors

key pieces of evidence that enhance the likelihood a crime will be solved

Proactive strategies

covert/undercover; usually involve police initiating investigative activities prior to the occurrence of a crime

Sting operations

undercover police attempt to buy/sell illicit goods

Decoy operation

undercover police attempt to attract criminal behavior

Undercover fencing operation

undercover police buy/sell stolen goods

Surveillance

police monitor activities of a person

Stakeouts

police watch a specific place

Entrapment

police induce or compel a person to commit a crime when that person is not predisposed to committing the crime

Information Theory

The idea that the criminal investigation process is a battle between the police and the perpetrator over evidence of the crime.

Probability error

possibility that coincidences are considered to be actual evidence

Tunnel Vision

When an investigator exclusively focuses on a particular person or range of alternatives and excludes other possibilities.

Confirmation bias

the tendency to interpret new evidence as confirmation of one's existing beliefs or theories.

Immovable mindset

The difficulty in changing one's theory about a crime and who committed it, even in the face of mounting contradictory evidence.

Overconfidence bias

the tendency to overestimate the accuracy of our beliefs and judgments and abilities

Groupthink

The phenomenon where a group's members tend to think alike and agree for the sake of group harmony. May cause individuals to self-censor ideas and opinions that go against group norms, or may be pressured by other group members to keep silent on these opinions.

Parliamentary reward

a system whereby a reward was offered by the government to anyone who brought criminals to justice or provided information that led to the apprehension of criminals

Informers

people who provided information about criminals in exchange for parliamentary reward (money)

Thief Takers

a person hired by the victim of a crime to recover stolen property and/or to bring a thief to justice

Thief Maker

a person who tricked people into committing crimes and then turned those people in for parliamentary reward

Rogues gallary

collection of photographs of known criminals

Bertillonage

a historical method of identification based on a series of body measurements

Dragnet

a method of investigation in which the police would bring in for questioning all the suspects who could have committed that crime

third degree

The physically brutal interrogation of suspects by police.

Judicial evidence

evidence that meets the rules of evidence and is admissible in court

Extrajudicial evidence

any information upon which an investigative decision can be based but the evidence is not allowed in court

Exculpatory evidence

any information having a tendency to clear a person of guilt or blame

Inculpatory evidence

Evidence that suggests the defendant's guilt.

Proof

certainty that a particular fact or circumstance is true

Standards of proof

different levels or degrees by which uncertainty about a fact can be eliminated

Probable cause

A standard of proof that requires evidence sufficient to make a reasonable person believe that, more likely than not, the proposed action is justified.

beyond a reasonable doubt

The standard of proof necessary to find a defendant guilty in a criminal trial.

Reasonable Suspicion

the standard of proof that is necessary for police officers to conduct stops and frisks

Preponderance of the Evidence

a standard of proof relevant in civil law and trials

Direct Evidence

Evidence that directly proves a fact without inference or presumption and which, in itself, if true, conclusively establishes that fact.

Indirect evidence

evidence that requires inferences in order to draw a conclusion; also known as circumstantial evidence

Testimonial evidence

Evidence that is presented in court through witnesses speaking under oath

Lay witness

persons who provide testimonial evidence based on facts personally observed

Expert witness

persons who provide testimonial evidence based on expert knowledge of a particular issue

Hearsay

A form of testimonial evidence that is secondhand or repeated information

Real evidence

physical evidence - such as a weapon, records, fingerprints, and stolen property - involved in the crime

Demonstrative evidence

Tangible objects produced indirectly from a crime that relate to the crime or the perpetrator.

Documentary evidence

evidence in document form

corpus delicti evidence

Refers to evidence that establishes that a crime actually occurred

Corroborative evidence

evidence that supplements and strengthens already existing evidence

Cumulative evidence

Evidence that duplicates but does not necessarily strengthen already existing evidence.

Associative evidence

evidence that links people, places, and things to each other

Identification evidence

Evidence that leads to the identification of the perpetrator

Behavioral evidence

Forensic evidence which suggests certain behaviors used to profile

Arrest

occurs when a police officer takes a person into custody or deprives a person of freedom for having allegedly committed a criminal offense

Custody

not free to leave

Arrest warrant

a court-ordered document authorizing the police to arrest an individual on a specific charge

Search

a government actor's infringement on a person's reasonable expectation of privacy for the purpose of discovering things that could be used as evidence in a criminal prosecution

Search Warrant

a document issued by a judge that authorizes law enforcement officers to search a person's property or possessions

Relevant evidence

evidence that relates to the case at hand

Material evidence

evidence that is significant and can help prove a fact

Competent evidence

evidence that is valid and of quality

Frye test

a legal test to determine whether scientific evidence is admissible; evidence must be generally accepted by the scientific community

Daubert Standard

a legal test to determine whether scientific evidence is admissible; evidence must be based on scientific knowledge

Necessary evidence

evidence used to establish a legitimate point, not to simply arouse feelings or to shock

Chain of Command

record of individuals who maintained control over the physical evidence from the time it was obtained by the police to when it was introduced in court

Exigent Circumstances

emergency circumstances that make obtaining a warrant impractical, useless, dangerous, or unnecessary, and that justify warrantless arrests or entries into homes or premises.

Vehicle exception

An exception to the search warrant requirement that allows the police to search a vehicle with reasonable suspicion (for weapons) or probable cause (for evidence).

Pretext Traffic Stop

a traffic stop made for any traffic offense that then allows for other law enforcement action

Other places exception

an exception to the search warrant requirement that allows the police to search places and things where people do not have a reasonable expectation of privacy

Hot pursuit expectation

an exception to the search warrant requirement that allows the police to enter a home, conduct a search, and make an arrest if they are in the pursuit of the subject and have a probable cause to believe the subject committed a crime

search incident to arrest exception

An exception to the search warrant requirement that allows the police to search a person and his or her immediate area when that person is arrested.

Stop and frisk exception

An exception to the search warrant requirement that allows the police to search the outer clothing of a subject for weapons based on reasonable suspicion criminal activity is afoot.

Plain view exception

an exception to the search warrant requirement that allows the police to seize evidence when that evidence is in plain sight of the officer

Consent exception

an exception to the search warrant requirement that allows the police to conduct a search when they receive consent to do so

Knock and talk search

a search in which the police talk with the occupant of a home in an attempt to get consent to conduct a search

Exclusionary rule

rule stating that if a search was unreasonable, evidence seized from that search is not admissible in court

Miranda warnings

a list of the rights that must be provided to an individual when in custody and prior to interrogation

If extrajudicial evidence cannot be used in court because it is inadmissable evidence, what purpose does it serve officers?

Although they cannot be used and brought up in court, they can be instrumental in the investigative process. Usually, it is what would be considered hearsay in a courtroom, but it is extrajudicial if it is said anywhere else. Or a polygraph test result is another example.

What is the difference between probable cause and beyond a reasonable doubt

Probable cause is a standard of proof that is necessary to make an arrest or justify searches, while beyond a reasonable doubt is the standard of proof necessary to obtain a conviction of a defendant

What are different types of circumstantial evidence?

a persons physical ability to commit a crime, alibi or lack of alibi, modus operandi, existance of identifiable motive, if an individual is found to be in possession of the fruits of the crime, the existance of prior threats made by a suspect, character witness

What is a character witness?

a person who has sufficient personal knowledge of another individual. opinion based, reputation based.

What are examples of expert witness specialties?

ballistics comparison, DNA analysis, estimation of time of death

What are some concerns about the reliability of hearsay?

the person who made the original statement was not under oath, or perhaps the person who made the original statement cannot be cross-examined (for example, they are now dead).

Who are the different people that could read investigative reports?

Officers, investigators, attorneys, judges, or citizens.

What are some basic rules for writing a good report?

It should be well organized, it should be in past tense, it should be detailed, and it should be objective

What are three requirements for a valid search warrant?

The search warrant paperwork itself, the affidavit that provides facts to establish probable cause, and the search warrant inventory+search

The 3 categories of incompetent evidence are?

evidence wrongfully obtained, statutory incompetency, and hearsay evidence.

What are the issues affecting the legality of a knock and search?

the walk: approach premises using accessible means, the encounter: , the knock, and the talk

Physical evidence

Also called real/forensic; physical evidence refers to any material object that may play a role in the matter that led to the litigation at hand. Most commonly, physical evidence will consist of objects found at the scene of a crime, example being a possible weapon

Class characteristics

features of forensic evidence that allow it to be associated with a group of sources

Individual characteristics

features of forensic evidence that allow it to associated with a particular source

Crime scene

The location where a crime has been committed or any place that evidence relating to a crime may be found.

Cross-contamination

occurs when investigators inadvertently transfer evidence from one scene to another

neighborhood canvass

A door-to-door search of the area of a crime to identify witnesses

DNA

Deoxyribonucleic Acid: The genetic building block of all living organisms and unique to an individual, except identical twins. Found in skin, hair, saliva, blood, and dandruff......

CODIS (Combined DNA Index System)

National database of DNA data obtained from individuals convicted of sexual assaults or homicides

DNA analysis

The process of extracting DNA from cells.

Familial DNA searching (genealogy)

searching for similar but not exact DNA matches

Biological evidence

body fluids, hair, plant parts, natural fibers

AFIS (Automated Fingerprint Identification System)

database containing fingerprints from various known sources