The Crime Scene. Crime Scene When the police arrive at the crime scene they usually do three things: When the police arrive at the crime scene they usually

The Crime SceneThe Crime Scene

Crime SceneCrime Scene

When the police arrive at the crime When the police arrive at the crime scene they usually do three things:scene they usually do three things: Call an ambulance and assist any Call an ambulance and assist any

injured people.injured people. Call for help or backup if needed.Call for help or backup if needed. Search the crime scene for witnesses, Search the crime scene for witnesses,

the the perpetratorperpetrator or evidence. or evidence.


The police establish two boundaries to The police establish two boundaries to protect the crime scene.protect the crime scene.

The The centercenter is where the incident occurred. is where the incident occurred. They also create a They also create a perimeterperimeter to keep people to keep people from entering.from entering.

Crime scenes are preserved for three Crime scenes are preserved for three reasons:reasons: To allow for a thorough search of the areaTo allow for a thorough search of the area To collect physical evidenceTo collect physical evidence And to ensure evidence collected is useable in And to ensure evidence collected is useable in

court.court.


Police Police protectprotect and and preservepreserve evidence by documenting the scene evidence by documenting the scene carefully and accurately.carefully and accurately.

Investigators keep a Investigators keep a police log police log which is a written record of what which is a written record of what each officer has witnessed at a crime each officer has witnessed at a crime scene or has learned from scene or has learned from questioning questioning witnesseswitnesses or or suspectssuspects..


There are four types of police officers There are four types of police officers involved at a crime scene.involved at a crime scene.

The first is the The first is the Patrol Officer Patrol Officer who is who is responsible for a certain area or responsible for a certain area or “beat”. He or she is usually the first “beat”. He or she is usually the first officer on the scene. They establish officer on the scene. They establish the perimeter by wrapping yellow the perimeter by wrapping yellow tape and conduct questioning.tape and conduct questioning.


The The Scenes of Crime Officer Scenes of Crime Officer is is trained in evidence collection. They trained in evidence collection. They take photographs, fingerprints and take photographs, fingerprints and foot impressions along with blood foot impressions along with blood and hair evidence.and hair evidence.

The The Criminal Identification Officer Criminal Identification Officer is responsible for searching the is responsible for searching the scene for physical evidence and scene for physical evidence and sending it to the laboratory for sending it to the laboratory for analysis.analysis.


The The Criminal Investigations Criminal Investigations Officer Officer is dressed in plainclothes is dressed in plainclothes and is specialized in a particular area and is specialized in a particular area such as homicide or robbery.such as homicide or robbery.

They supervise the whole They supervise the whole investigation, interview witnesses, investigation, interview witnesses, interrogate suspects, draw interrogate suspects, draw conclusions from physical evidence, conclusions from physical evidence, and arrest suspects.and arrest suspects.


Physical EvidencePhysical Evidence may defined as any may defined as any object, impression, or object, impression, or body element that can body element that can be used to prove or be used to prove or disprove facts relating disprove facts relating to an offence.to an offence.

Forensic ScienceForensic Science is is the application of the application of biochemical and other biochemical and other scientific techniques to scientific techniques to criminal investigation.criminal investigation.


Often at the scene Often at the scene of a crime of a crime impressions are impressions are left. left. ImpressionsImpressions are marks or are marks or patterns caused by patterns caused by different objects different objects such as fingers, such as fingers, gloves, shoes, gloves, shoes, tires, or tools.tires, or tools.

Crime SceneCrime Scene Impressions have two Impressions have two

characteristics: characteristics: class class characteristicscharacteristics and and individual individual characteristicscharacteristics. . Class Characteristics Class Characteristics are general attributes are general attributes of an object such as of an object such as type, make, model, type, make, model, size, and style. size, and style. Individual Individual CharacteristicsCharacteristics deal deal with specific traits of with specific traits of an object such as tire an object such as tire ware or a scratch on a ware or a scratch on a car.car.

Crime SceneCrime Scene Fingerprints are Fingerprints are

patterned marks left patterned marks left on a surface by a on a surface by a fingertip. Prints are fingertip. Prints are unique to each unique to each individual and never individual and never change.change.

There are two types of There are two types of fingerprints: Visible fingerprints: Visible and latent. Visible and latent. Visible prints can be seen as prints can be seen as where latent prints where latent prints must be dusted or must be dusted or illuminated.illuminated.


Crimes against people Crimes against people usually result in the usually result in the loss or transference of loss or transference of bodily fluids.bodily fluids.

Police can use these Police can use these fluids along with hair fluids along with hair and skin samples to and skin samples to identify a persons identify a persons DNA.DNA.

DNA is like fingerprints DNA is like fingerprints and is unique to every and is unique to every individual.individual.


The proper labeling of The proper labeling of evidenceevidence is is important so it can be identified at a later important so it can be identified at a later date.date.

Police officers establish a proper Police officers establish a proper chain of chain of custodycustody for the evidence or a written record for the evidence or a written record of everyone that has handled the evidence.of everyone that has handled the evidence.

A chain of custody must show:A chain of custody must show: Who had contact with the evidenceWho had contact with the evidence The date and time the evidence was handledThe date and time the evidence was handled The circumstances and reasons for the handling The circumstances and reasons for the handling

of the evidenceof the evidence What changes were made to the evidenceWhat changes were made to the evidence

Crime SceneCrime Scene All evidence collected at the scene of the All evidence collected at the scene of the

crime is tagged and placed in and “evidence crime is tagged and placed in and “evidence package”. The following information usually package”. The following information usually appears on both the tag and the exterior of appears on both the tag and the exterior of the package:the package: Brief descriptionBrief description Police case numberPolice case number Date of collectionDate of collection Location of collectionLocation of collection Brand name of the itemBrand name of the item Serial number or clothing informationSerial number or clothing information Name and badge number of the officer collected itName and badge number of the officer collected it Destination of the evidenceDestination of the evidence


A person who is A person who is detaineddetained by a by a police officer is taken into custody police officer is taken into custody without the use of physical restraint.without the use of physical restraint.

The police usually detain a person for The police usually detain a person for such things as questioning. such things as questioning. The The person being detained must be person being detained must be informed of the reasons for the informed of the reasons for the detention and their right to detention and their right to retain counselretain counsel (lawyer).(lawyer).


Police interrogate or Police interrogate or ask a suspect questions ask a suspect questions with four goals in mind:with four goals in mind: To get a description of To get a description of

the incidentthe incident Information about the Information about the

time before the incidenttime before the incident The details around the The details around the

offenceoffence What happened after the What happened after the

offenceoffence

Crime SceneCrime Scene If a person is arrested If a person is arrested

they are formerly taken they are formerly taken into police custody.into police custody.

In order for an arrest to In order for an arrest to be lawful the police be lawful the police must:must: Identify themselves as a Identify themselves as a

police officerpolice officer Advise the accused they Advise the accused they

are under arrestare under arrest Inform the accused the Inform the accused the

chargescharges Physically touch the Physically touch the

person to indicate they person to indicate they are in custody.are in custody.


In order for a police officer to arrest In order for a police officer to arrest someone they need someone they need reasonable reasonable grounds.grounds.

For example if Wendy was sitting in a For example if Wendy was sitting in a car with bags full of money after a car with bags full of money after a nearby bank was robbed. The police nearby bank was robbed. The police would have would have reasonable groundsreasonable grounds to to arrest her.arrest her.


The police have three methods of The police have three methods of apprehending an offender:apprehending an offender: An An appearance noticeappearance notice is given at the scene is given at the scene

of a crime that is less serious.of a crime that is less serious. A A summonssummons is a legal document given to a is a legal document given to a

person who the police believe will not appear person who the police believe will not appear in court voluntarily.in court voluntarily.

An An arrest warrantarrest warrant is a legal document giving is a legal document giving the police the authority to arrest or detain a the police the authority to arrest or detain a person who is suspected of having committed person who is suspected of having committed a crime.a crime.

Crime SceneCrime Scene A A citizen’s arrestcitizen’s arrest is an arrest without a is an arrest without a

warrant by any person other than a peace warrant by any person other than a peace officer.officer.

Section 494 of the Section 494 of the Criminal CodeCriminal Code says says Anyone may arrest without warrant Anyone may arrest without warrant

A person found committing an indictable offenceA person found committing an indictable offence A person who 1) has committed a criminal offence 2) A person who 1) has committed a criminal offence 2)

is escaping from and pursued by a person who has is escaping from and pursued by a person who has the authority to arrest.the authority to arrest.

Anyone who is Anyone who is The owner of propertyThe owner of property A person authorized by the owner of property may A person authorized by the owner of property may

arrest a person he finds committing a criminal arrest a person he finds committing a criminal offence on or in relation to that property.offence on or in relation to that property.


The police do not need a The police do not need a warrantwarrant to to search a person they just arrested.search a person they just arrested.

The arrested person does not have to The arrested person does not have to supply the police with a breath, blood supply the police with a breath, blood , or urine sample unless they are , or urine sample unless they are arrested for arrested for impaired drivingimpaired driving..

The police are allowed to conduct The police are allowed to conduct strip searches under very strict strip searches under very strict guidelines.guidelines.

Crime SceneCrime Scene In order to search a dwelling the police need to In order to search a dwelling the police need to

obtain a search warrant.obtain a search warrant. The search must be conducted between The search must be conducted between

6:00am and 9:00pm and the police must 6:00am and 9:00pm and the police must identify themselves and provide the warrant.identify themselves and provide the warrant.

In the case where police suspect a person of In the case where police suspect a person of having illegal drugs they may search buildings having illegal drugs they may search buildings without a warrant. They also may search a without a warrant. They also may search a dwelling without a warrant if they believe it dwelling without a warrant if they believe it prevents imminent danger or the destruction of prevents imminent danger or the destruction of evidence.evidence.

Police are also allowed to search vehicles Police are also allowed to search vehicles without a warrant.without a warrant.

Crime SceneCrime Scene Once a person has been arrested, fingerprinted, Once a person has been arrested, fingerprinted,

and photographed, the police will often release the and photographed, the police will often release the accused until the trial.accused until the trial.

If the police are not afraid of the accused fleeing If the police are not afraid of the accused fleeing trial they will just have them sign a trial they will just have them sign a promise to promise to appearappear. If they fail to show an arrest warrant will . If they fail to show an arrest warrant will be issued.be issued.

In some cases the accused may be asked to sign aIn some cases the accused may be asked to sign a recognizancerecognizance-which is a promise to appear or a -which is a promise to appear or a fine may be charged. Afine may be charged. A surety surety, a person willing to , a person willing to pay the fine in case the accused doesn’t show, may pay the fine in case the accused doesn’t show, may also be asked for.also be asked for.

Police will try and keep dangerous offenders in jail Police will try and keep dangerous offenders in jail until trial. In this case a suspect can post until trial. In this case a suspect can post bailbail. . BailBail is a some of money is a some of money

Documents

The Crime Scene. Crime Scene When the police arrive at the crime scene they usually do three things: When the police arrive at the crime scene they usually