6.1 - Criminal Investigations

Investigating Criminal Offences

Understanding the nature of criminal offences in Canada is one thing; but, it is another thing entirely to investigate alleged crimes, with the intended end result being a criminal conviction.  Criminal law in Canada is founded on two key principles.  First, everyone is innocent until proven guilty.  It is not up to the accused person to prove their innocence.  Rather, it is up to the Crown to prove their guilt.  Second, not only does the Crown need to prove the guilt of the accused; but they also must prove guilt beyond a reasonable doubt.  This means that the proof of guilt is strong enough that a reasonable person would have almost no doubt that the accused person is guilty.  The remainder of this section will discuss how criminal investigations are conducted, and who are the participants in such investigations.

Who Conducts Criminal Investigations?

Criminal investigations are conducted by one of four major types of police forces in Canada.  The first type is federal police.  The Royal Canadian Mounted Police (RCMP) takes the role of federal police in Canada, and takes on specific crimes related to border integrity, drugs and organized crime, international policing, and financial crime, to name a few.  The second type of policing is provincial police.  Ontario, Quebec, and Newfoundland and Labrador have a provincial police force.  These forces have jurisdiction in rural and unincorporated areas.  In the other provinces and territories, it is the RCMP that acts as the provincial police.  Third, municipal police provide policing services within cities and incorporated towns.  Municipal police may be independent (as in the Vancouver Police Department), or a city’s policing services may be contracted to the RCMP, who then take the role of municipal police in the city (as in the Kelowna RCMP).  Finally, Aboriginal police exist as the fourth type of policing in Canada.  These forces may be established to provide policing services to residents of First Nations reserves.  Whatever the level of police force, criminal investigations are conducted according to the guidelines in statute and case law.

Steps in Investigating Crime Scenes

Criminal investigations typically begin at the crime scene.  This is the location where a crime took place.  The center of the crime scene is the focal point - the area where the crime actually occurred; whereas, the perimeter of the crime scene is the area around the center.  The perimeter is important as it may contain some evidence.  Investigating a crime scene typically involves the following four general stages:  arriving at the crime scene, documenting and evaluating the scene, processing the scene, and completing and recording the crime scene investigation.

Stage 1:  Arriving at the Crime Scene

Police officers that are dispatched to crime scenes are typically general duty officers.  These officers are first to arrive at the crime scene, and have several key jobs to do immediately.    First, they need to ensure that the site is safe for themselves and others.  Second, they will provide support for any injured people (first aid, call paramedics).  Third, once they’ve confirmed site safety, they may call for back-up (if needed).  The fourth key role during this time is to secure and control people at the crime scene.  People at the scene may be agitated, so officers try to establish calm.  Fifth, police will identify, establish, protect, and secure the crime scene boundaries so that there is no contamination of the scene.  Crime scene contamination is when there is a loss, destruction, or alteration of physical evidence.  Finally, the first officers on the scene will begin the process of documenting their actions and observations, often to hand over to other police specially trained in the collection of evidence.

Stage 2:  Documenting & Evaluating the Crime Scene

The second stage of a crime scene investigation involves police collecting and documenting more specific information from the scene.  That is, they conduct a ‘deeper dive’ into the examination of the crime scene.  This information may include statements from witnesses and eyewitnesses, as well as an immediate detailed accounting (including photographs) of all evidence at the scene.  This stage may be handled by general duty officers (if it’s a relatively minor offense), or by specially trained scenes or identification officers (if it’s a more serious crime).  Also, if the crime is a serious one, a special investigator may be called in. These are specialist detectives that take a lead role in the investigation.  IHIT, or Integrated Homicide Investigative Team, is one example of these special investigators.  This team investigates all homicides in the Lower Mainland.  Once this process of documenting and evaluating the evidence has begun, it continues through the next stage.

Stage 3:  Processing the Scene

The collection and evaluation of physical evidence in the previous stage continues here, only in more and more detail.  Physical evidence refers to any object, impression, or body element that could be used to prove or disprove facts related to an alleged crime.  Impressions refer to patterns or marks found on surfaces and caused by various objects.  Impressions are examined in terms of their class characteristics (general attributes), as well as their individual characteristics (specific and unique features of an object).  For example, a class characteristic might be from a Nike shoe; whereas an individual characteristic is the specific tread pattern on a specific Nike shoe model.  A few examples of sources of impressions include fingerprints, gloves, shoe/footprints, and tire tracks.  Fingerprints may be visible fingerprints (print formed when finger is coated with blood, grease, etc. and is visible to the naked eye), or latent fingerprints (print formed by natural skin oils and perspiration, and are not visible to the naked eye).  Body element evidence includes the collection of substances such as blood, hair, semen, sputum (spit), skin, or mucus.  These elements are often subjected to forensic science (CSI) testing.  Forensic science uses various biochemicals (like DNA testing) and other scientific techniques to analyze evidence in criminal investigations.  The amount of time and effort expended by police in this stage depends on how serious the crime is, and how complex the crime scene is.

Stage 4:  Completing & Recording the Crime Scene Investigation

The final stage of the crime scene investigation includes the final survey of the scene, and the collation of all of the evidence.  Evidence that is collected at the scene must be handled carefully, as well as packaged and labeled accurately, so as to not contaminate any key evidence.  Police work hard to establish a chain of custody for all evidence.  Chain of custody refers to a written record of people who had contact with each piece of physical evidence.  This is important to ensure that the evidence remains completely objective, and thus may be used in trial.  Once the above four stages of investigating crime scenes have been completed, it usually does not mark the end of the investigation itself.

Investigating Beyond the Crime Scene

Obviously, the investigation of a crime scene is critical to solving the crime, and identifying the accused.  However, most investigations continue beyond what is found at the crime scene.  Police will seek out witnesses that may have information that proves, or disproves, the identification of a suspect.  Also, other witnesses may help police to prove that the suspected criminal actually committed the criminal act.  Once the suspect has been identified, and sufficient proof obtained, then the police may proceed to arrest the suspect.  Arrest and detention will be the focus of the next section, 6.2.