Main Body

Chapter 5: Strategic Investigative Response

“The STAIR model is a tool a new investigator can use to start structuring and developing their own investigative thinking processes.”

In this chapter, we will examine the operational processes of investigation. To this point, we have examined many definitions, concepts, and response protocols to set the stage for embarking on the strategic investigative response. If it can be said that there is a creative art anywhere in the processes of investigation, the strategic investigative response is where that creative art takes place. In this chapter, you will learn how each of the following concepts and processes relates to the strategic investigative response:

  1. Avoiding the three big investigative errors
  2. Recognizing the transition and implementing the strategic investigative response
  3. Describing investigation as a process within the justice system
  4. Utilizing the STAIR tool to work through the investigative process

Topic 1: Avoiding the Three Big Investigative Errors

In very fundamental terms, the three most common errors of the Strategic Investigative Response are:

  1. Failing to identify and collect all the available evidence and information,
  2. Failing to effectively analyze the evidence and information collected to identify suspects and form reasonable grounds to take action, and
  3. Becoming too quickly focussed on one suspect or one theory of events and ignoring evidence of other viable suspect or theories that should be considered.

From the moment a police investigator is dispatched to attend an incident, the opportunity to gather and evaluate information and evidence occurs. It is not uncommon for new investigators to operate under the misconception that all the available evidence and information is going to be readily available and apparent to them at the scene. This is the misconception behind Error #1: failing to identify and collect all the available information and evidence. New investigators often don’t understand that some information and evidence can be elusive and will exist in secondary source locations that must be sought out. There is no room for complacency in the processes of collecting information and evidence. The investigator must be engaged at an elevated level of awareness to access secondary source locations. Information and evidence about the event needs to be actively looked for, recorded, and preserved in a manner that can analyzed, interpreted, and eventually presented in court.

In the first instance of collecting information and evidence, an investigator may become engaged in the process through several different means. It may be receiving information as circumstances provided by the dispatcher in the details of a 911 call, it may be a report from a citizen on the street, or it may even be an on-view situation where the investigator discovers a crime in progress. From the moment the process begins, information will be incoming and available in the form of things that are seen and heard personally by the investigator, and this includes witnesses statements received. In most investigative responses, these are the first level facts that the investigator receives to guide the immediate event classification and offence recognition. But, this information of initial complaint and first observations are not all the information that might be available. There is usually much more information and evidence to be found. This is where the extended task of information gathering begins. Consideration of pre-crime and post-crime activities of the suspect can produce evidence not available at the crime scene. Database searches for records of the suspect, victim, and witnesses, can have great value. This is where the investigator must proactively search. There are many possible sources of additional information and evidence to consider, such as:

  • CPIC (Canadian Police Information Center) for criminal records info, outstanding warrants and pointers to criminal association
  • Police RMS (Record Management Systems) PRIME AND PROS databases to provide information on past records of complaints, investigations of criminal activities, and historical criminal associations
  • ViCLAS (Violent Crime Linkage Analysis System) provides a database of searchable criminal conduct acquired from the past crimes of known offenders
  • MVB (Motor Vehicle Branch) records for current vehicles registered, driving record, physical descriptors, and resident address

These information data sources can all add to the personal observations made by the investigator regarding the scene of the crime. These along with the appearance and demeanor of suspects, victims, and witness; and information provided by those suspects, victims, and witnesses about the event can speak volumes. Now, add to this the physical exhibits of evidence specific to the criminal event as each of these might have meaning in their immediate form or may provide future meaning through forensic analysis.

Having gathered all of the available information from each of the possible sources and locations we have avoided making Error #1.

To avoid making Error #2, we must now analyse the information we have collected. It is not just information about the event and the fact-pattern that are important, it is also information about the people involved in the event and how they are connected within the fact pattern. Criminal records and police records of each person associated to the incident can provide valuable perspectives, such as people’s reputation, credibility, association to past criminal conduct, or even event-related connections between the players.

Evidence and information gathered about the event only exists at face value until the investigator undertakes the proactive process of evaluation and analysis to determine the information’s relevance to the investigation at hand. It may seem that the implications and meanings of the available information and evidence should be clear and, sometimes in simple investigations, it is clear. Sometimes, what you see is what you get. If there are eyewitnesses describing a clear fact pattern and an identified suspect, the investigation will be a straight forward matter of collecting the evidence for presentation to the court.

That said, it is not often that simple in criminal investigations. Frequently, a suspect has not yet been identified and the fact pattern of the crime is unclear. Without a proactive process of evidence analysis, it is not possible to reconstruct the event and recognize the implications and connections within the multiple layers of evidence and information. The indicators of motive, opportunity, and means may not be immediately apparent. If an investigator goes to a criminal event and all they do is record the facts at face value and collect the evidence that is visible on-site, the job is only half complete. They are merely recording the crime.

The outcomes of analyzing information and physical evidence can be truly significant. A focussed effort to analyze physical evidence and information can often yield results that contribute to establishing a fact pattern, identifying a suspect, and forming reasonable grounds for arrest and charges. Let us consider again the example of the British Bow Street Runners (Hitchcock, 2015) who located a piece of wadding paper from the fatal bullet wound in the head of their victim. At that time, wadding paper was typically used when loading any firearm as a plug to compact the powder and direct the explosive force that discharged the bullet. Investigators could have easily recorded this exhibit and dismissed it as just another piece of wadding paper. Instead, they considered the implications. Their analysis of the information and evidence was done by comparing the torn edges of that wadding paper and making a physical match to the originating piece of wadding paper that was found in the pocket of their suspect. This critical piece of circumstantial evidence made the connection between the suspect and the crime, and it led to a conviction in court.

Error # 3 is commonly known as “tunnel vision”. Over the years, commissions of inquiry into wrongful convictions have often determined that investigators in those cases had allowed themselves to fall prey to tunnel vision (MacCallum, 2008; Kaufman, 1998), This tendency to focus on a single suspect or a single theory of events can be pervasive, and even when other viable suspects are present and the physical evidence does not support their theory, investigators have been seen to continue with a single minded focus. Tunnel vision has happened frequently enough that investigators are now cautioned to be self-aware that anyone can fall prey to this error. As part of proper major case management, investigative team members are encouraged to challenge each other when they believe that evidence is being misinterpreted and a single suspect or theory is being exclusively pursued to the point where other viable suspects and theories are excluded or ignored.

Topic 2: Recognizing the Transition and Implementing the Strategic Investigative Response

As much as the tactical investigative response is driven by urgent circumstances that require immediate and decisive action to reach successful outcomes, strategic investigative response is driven by the complexity of circumstances. The investigator will need to take a slower and more deliberate approach. This means observing the rules of law that are more demanding of due process and the rules of evidence that are more demanding of adherence to protocols for crime scene management, evidence preservation, and evidence collection.

The situational elements that define a strategic investigative response are essentially the opposite of those for tactical investigative response. Specifically, the scene is now an inactive event because the suspect has left the scene or has been arrested, and there is no ongoing explicit or implied danger to the life or safety of persons including police. In the strategic investigative response, the Level Two priorities of protection of property, gathering and preserving of evidence, accurately documenting the event, and establishing reasonable grounds to identify and arrest suspects now become the paramount concerns. Switching from a tactical investigative response to a strategic investigative response is a transition point where mistakes can occur. These mistakes happen because the need to shift is not recognized and the transition to Level Two priorities is not engaged. The switch from an active event and tactical response to an inactive event and strategic response means locking down the crime scene to protect evidence and obtaining a warrant to continue the search for evidence.

This failure to transition may happen because the officers attending the scene of an active event are intensely focussed on the issues of protecting life and safety. Once those very critical issues of life and safety are resolved, the adrenaline is still flowing and shift to Level Two priorities can seem less significant than it really needs to be. Investigators need to be aware and recognize the requirement to transition to strategic investigative response and make it happen.

Topic 3: Describing the Investigation Process Within the System

Strategic investigative response process is slow-paced and deliberate. In this response there is a priority to collect and record the maximum amount of information and evidence for court. These tasks of strategic response include witness management, crime scene management, evidence collection, and documenting the event.

Once the determination has been made that the investigation is in strategic investigative response mode, the priorities for results change, and the investigator must start organizing their investigation of the crime being encountered. In cases where the circumstances are simple and the suspect is immediately apparent, this can be a straightforward matter of evidence collection and witness interviews. In other cases, where the facts of the case are not clear or the suspect is not immediately apparent, the tasks of investigation can be daunting, and it requires a more systematic approach. A thorough investigation is one with systems to:

  • Identify and collect all available evidence,
  • Identify all the witnesses, victims, and possible suspects,
  • Accurately document the criminal event,
  • Accurately document the investigative actions,
  • Develop theories of how the crime was committed and who may be a suspect, and
  • Formulate an investigative plan to form reasonable grounds and make an arrest.

It may be helpful to think about the Strategic Investigative Response like a big funnel where many sources of information and evidence pour data into the top of the funnel. That data passes through the investigative filters of analysis to determine the possibilities, developing theories to identify the best probabilities, and investigating to test those theories against known evidence and facts. It narrows itself down to inculpatory evidence that will support reasonable grounds for belief, or exculpatory evidence that will show innocence and eliminate suspects. Sufficient inculpatory evidence can tip the scale to give police reasonable grounds for belief to take action of arrest and finding proof of guilt beyond a reasonable doubt provides the court with the ability to make a finding of guilt. Exculpatory evidence tips the balance to support the presumption of innocence for the accused.


Topic 4: Utilizing the STAIR Tool to Work Through the Investigative Process

At this point in our study of the investigative process, it is necessary to examine a structured process for strategic investigative response. To illustrate a system for strategic investigative response that can assist an investigator in thinking through the investigative process, we will use a model called the STAIR tool. Organized thinking and the ability to articulate a structured response cannot flow from a disorganized process. Through experience over time, most police investigators learn to structure their thinking, their investigative process, and their response priorities. Each investigator learns to build one’s own mental road map.

The methods and mental mapping of the STAIR tool illustrated here are not an attempt to change the current reality of investigative thinking, it is merely the model of a process to illustrate the thinking used by many investigators. A new investigator can use this tool to start structuring and developing an investigative thinking processes.

Every day, operational police officers are tasked to respond to incidents in a never ending variety of scenarios. Arriving at the scene of an incident, the police investigator is usually at the disadvantage of not knowing many of the facts. The investigator is challenged to gather the available information and analyze what is relevant with a goal of responding quickly, effectively, and appropriately. An effective and appropriate response is a response where the investigator has made decisions according to a predetermined set of priorities. For the investigator, these priorities and the desired results should always be protecting the life and safety of persons, protecting property, gathering and preserving evidence, accurately documenting the event, and establishing reasonable grounds to identify and arrest offenders. With these results in mind, we can start by remembering that in every reported incident, a police investigator is met with a situation Situation that must be resolved. With this situation understood immediate Tasks must then be undertaken to protect life and safety, gather relevant information, preserve evidence, and identify offenders. Lastly, in every situation, the information discovered must be Analyzed to inform and guide the Investigation that must happen to reach the desired Results.

To become more self-aware, an investigator might imagine oneself working through this process and creating a mental map of the road to be traveled for each investigation. This mental map can later be articulated, describing one’s thinking process and responses, observing the law as rules of the road, describing landmarks of evidence, navigating curves in the fact patterns, backing out of the dead ends of false leads, and validating the evidence discovered that led to a final destination. Ideally, that destination is the positive identification of a suspect and sufficient evidence to make an arrest and provide the court with proof beyond a reasonable doubt.

Later, when preparing notes, reports, court briefs, and testifying in court, the investigator will be able to recall their mental map and articulate their decision-making process to form the necessary reasonable grounds for belief to take action. If the crime remains unsolved and the investigation concludes as a cold case, the notes and reports describing the mental road map of the investigation remain on file for the next investigator who will be able to gain a clear picture of the investigation to date.

SITUATION: achieving a big picture view of the event to classify and prioritize a response

  • Break out the known facts of the event
  • Offence classification – active event or inactive event
  • Identify all the players – victims, witnesses, and suspects
  • Offence recognition – identify the possible offence or offences being encountered

TASKS: focus on the results and the priorities of those results based on event status

  • Tactical investigative response on active event – Level 1: resolve life and safety issues
  • Strategic investigative response on inactive event – Level 2: priorities engaged
  • Crime scene management – evidence identification, evidence preservation, and evidence collection
  • Canvassing for witnesses – witness interviewing
  • Profiling the players – use all police data base information – CPIC, PRIME, PROS
  • Document the event – notes, reports, photographs, diagrams, videos

ANALYSIS: examining the reported facts, the observed facts, and the physical evidence

  • Make observations and connections between people and circumstances
  • Enhance the meaning of physical evidence by forensic analysis
  • Determine evidence of motive, opportunity, and means to commit the offence
  • Create timelines of activities
  • Develop assumptions and theories that will guide the investigative process
  • Develop investigative plans based on theories
  • Authentication of the event – did it occur at the time, at the place, and in the manner being reported, or is the report a fabrication?

INVESTIGATION: validating the facts through corroboration of witness accounts and evidence

  • Prioritize the best investigative plans based on most likely theory
  • Test theories against information and evidence discovered through investigation to identify suspects and form reasonable grounds
  • Return to analysis to form new theories or modify theories as new facts are found

RESULTS: prioritizing and focussing on the results to guide the investigative process

  • Protection of the lives and safety of people
  • Protection of property
  • Gathering and preserving evidence
  • Accurately documenting the event
  • Establish reasonable grounds to identify and arrest suspects


Please note: The STAIR investigation tool as developed and depicted in this book is based on the author’s conceptual modification of the STAR technique which is commonly used as a tool for behavioural interviewing. 


In this chapter, we have focussed on the strategic investigative process and described the STAIR tool as a means of illustrating and working through the investigative process. This is a process that can be likened to climbing a set of stairs, whereby getting to the top (Results) requires taking one step at a time from the bottom (the Situation). The second step (Tasks) then leads to a third step (Analysis) and the fourth step (Investigation). At this point, the investigator can expect to take a step back more than once to do further Analysis. In any case, the goal is always to get to the top of the stairs. Skipping any of these steps will likely lead an investigator to miss an important part of the process.

As with the preceding chapters, the intent here is simply to assist you in defining and visualizing the investigative process. This delineation should help you to conceptualize investigation as a structured process. This is a process consisting of practices of information and evidence collection, analysis, theory development, and investigative planning, pointing toward achieving consistent outcomes. In the chapters that follow, you will be challenged to apply this thinking in some scenario exercises.


  1. What are the three most common errors investigators make in applying the Strategic Investigative Response?
  2. What five groups of tasks must an investigator follow through on to complete a thorough investigation?
  3. What categories of tasks are involved in the Situation component of the STAIR tool?
  4. What categories of tasks are involved in the Tasks component of the STAIR tool?
  5. What categories of tasks are involved in the Analysis component of the STAIR tool?
  6. What categories of tasks are involved in the Investigation component of the STAIR tool?
  7. What categories of tasks are involved in the Results component of the STAIR tool?