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13.1: ROBBERY INVESTIGATION

  • Page ID
    67603
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    In cases where the offender is not immediately identifiable, or the fact pattern of the event is not clear, the investigation becomes more complex and protracted. These are the cases where the strategic investigative response will include analyzing the information and evidence to develop theories, to identify possible suspects, and to test possible fact patterns against the physical evidence and timelines.

    To examine this process of strategic investigative response, we will look at a more complex scenario where additional skill sets and strategies need to be considered within the STAIR Tool (Gehl and Plecas, 2017).

    Scenario: Robbery

    You are in a marked patrol vehicle, and you are dispatched to attend a local jewelry store where a robbery has just taken place. It is August 15, 2017, 4 PM on Saturday. The store is in a strip mall complex on the main street of your city. You arrive at the scene to take the complaint and investigate.

    The store manager reports that at approximately 3:30 PM, three suspects entered through the front door of the store from the front parking lot. All three suspects were wearing ski masks, gloves, blue jeans, and dark jackets. All three were armed with handguns. One suspect stood guard at the front door and the other two entered the store yelling at everyone to lay face down on the floor. There were three customers in the store: two elderly women shopping together and one young woman approximately 25 years of age.

    There were also two store employees working at the time. One is the store owner/manager and the other is a female sales clerk. After everyone was on the floor, the two men started smashing glass display cases and dumping the contents into white cloth bags that they had with them. One robber demanded that the manager open the cash register, which he did. There was only approximately $350 in the cash register, which was typical because most customers use credit or debit cards. The manager estimates that approximately $120,000 worth of inventory was stolen. The most valuable items taken were diamond rings and highend designer wrist watches. Watches have serial numbers and are identifiable, and some of the diamonds are identifiable by laser micro-engraving.

    The entire robbery happened in just under five minutes and, when the robbers left the store, they ran south around the corner of the building. No vehicle was seen.

    STAIR Tool for Investigation

    Situation

    Using the STAIR tool, as you approach the scene, you are aware that the suspects have left the crime scene and this is an inactive event. Although aware of the possibility that you may see suspects leaving the area of the crime scene, your arrival and approach to the crime scene do not require the tactical investigative response of an active event. The immediate danger to the life and safety of persons at the crime scene has passed. You are in the strategic investigative response mode. Beginning with your end in mind, you now consider what will be the Results for this case:

    • Protecting the life and safety of persons at this crime scene is no longer an issue because the armed suspects have now left the scene
    • Protecting property will be an issue because $120,000 worth of merchandise and $350 in cash have been taken and need to be recovered
    • Gathering and preserving evidence will be an issue because there are witnesses to interview at the scene and possibly physical evidence left behind by the suspects
    • Accurately documenting the event will be necessary
    • Establishing reasonable grounds to identify and arrest offenders will certainly be the desired outcome

    Tasks

    With our Results priorities clearly in mind, you now undertake some specific Tasks of the STAIR tool:

    • Secure the crime scene
    • Examine the crime scene and call upon forensics for evidence collection
    • Broadcast a description of the suspects and incident details as a BOL
    • Identify all witnesses and victims present
    • Run each witness and victim through police databases to determine any criminal records, history of criminal conduct, or association to known criminals
    • Take individual statements from each witness and victim

    After completing your victim and witness interviews and your database searches, you have the first pieces of information from which the Analysis component can begin. Your forensic team is at the scene dusting for fingerprints and photographing the damage.

    Analysis

    As mentioned above, STAIR will assist in developing strategies to guide Investigation efforts. Based on the Strategic Investigative Response Funnel, all incoming information is flowed into the top of the funnel to start the process of analysis. The analysis begins by considering each of the individual known facts about the incident. In this case, the facts to be considered include:

    • Date of OFFENSE: Saturday August 15, 2012
    • Time: 4 PM
    • Location: jewelry store in down town strip mall
    • Owner/manager and one employee present (witnesses)
    • Two elderly women shopping together present (witnesses)
    • One 25-year-old female shopper present (witness)
    • Three apparently male suspects entered the store through front door
    • All suspects were wearing ski masks, gloves, blue jeans, and dark jackets
    • Each suspect had a handgun
    • One suspect stood guard
    • Two suspects entered the store
    • Suspects told everyone to lay on the floor
    • Suspects smashed display cases and loaded jewelry and watches into bags
    • Each suspect carried away the stolen goods in white bags
    • One suspect had the manager open the cash register and took $350 cash
    • Approx. $120,000 worth of jewelry was taken
    • Some of the watches and diamonds stolen are identifiable by serial numbers
    • Suspect fled out the front door and south around the corner of the building
    • No vehicle was seen
    • Entire robbery took under five minutes

    To continue this Analysis, we start by reflecting on some of the theories we might evolve considering the facts of this case. This will begin the process of developing theories and formulating investigative plans to identify suspects and search for new evidence that either confirms or disproves those theories.

    1. What theories might you have about the time and location of this OFFENSE?
    2. Can you develop any theories about the level of planning that went into the robbery?
    3. Consider theories about how well these three suspects know each other.
    4. Is it possible that the suspects had been at the store sometime prior to this robbery?
    5. What relevant theories might be considered from the way the suspects were dressed?
    6. What relevant theories might be considered from the fact that the robbers carried handguns?
    7. What theories might be considered from the way the robbery was carried out?
    8. What theories might be considered regarding the items taken?
    9. Theorize and consider if these three suspects were working alone.
    10. Theorize who else might be involved.

    Think about the fact pattern of this incident and answer these questions. In this process, you will engage your imagination and your deductive reasoning skills to consider the possibilities and develop theories to guide your investigative plan going forward. In this step of the Analysis process in the STAIR, what logical theories can you develop to explain how this crime may have been committed, and who may have been involved? Try and develop at least two or three alternate theories. As you answer each question, consider different avenues of investigation you might follow to confirm or disprove some of your theories. Can aspects of your theories be confirmed or disconfirmed against an examination of the existing physical evidence?

    Investigation

    As you proceed through the STAIR tool, the process of Analysis and Investigation can become somewhat circular, as the investigation reveals new information, and new information is analyzed to confirm, disprove, or modify the theories of suspects and events that you are considering.

    Do your theories present any avenues where you can investigate further to gain additional information?

    Outline your own analysis, assumptions, deductions, and theories. Outline the further avenues for investigations that you can undertake in this case. After you have completed your own analysis, theory development, and investigative plans, move to the end of this chapter and check your assumptions, analysis, theories, and investigative plans against the answers provided there.

    1. What theories might you consider about the time and location of this OFFENSE?
      • The fact that the jewelry store is in a strip mall may have been a factor in the robbers selecting this location as a target. This type of business premises allows for drive by viewing of the inside of the premises, as well as quick access and exit to the outside parking area. This location also allows for the suspects to maintain an ongoing look-out for approaching police response.
      • The time of the OFFENSE could have been intentionally chosen closer to the end of the day on a Saturday in the hope that more cash would be in the store. Depending on the typical customer traffic volume in the mall area on a Saturday, the suspects may have hoped for more traffic volume to assist with their escape.
    2. Can you develop any theories about the level of planning that went into the robbery?
      • Since the suspects arrived in disguise, armed with handguns, and carrying bags to take away the proceeds of the robbery, it might be theorized that they took some time to put together this special equipment to carry out the crime.
      • The precision with which the robbery was carried out (e.g. completed in five minutes, one suspect guarding the door, all persons ordered onto the floor) would indicate a high level of planning to orchestrate this robbery.
    3. How well did these three suspects know each other?
      • It is very likely that the three suspects knew each other well enough to establish the level of trust required to carry out the robbery.
      • The type of goods taken in this robbery, except for the cash, would need to be converted to cash to be divided up later. This could indicate that a longer-term relationship exists between these robbers.
      • The planning that is apparent would indicate that the suspects spent some time together to plan, collect the necessary equipment, and divide up the proceeds of the robbery.
    4. Is it possible the suspects had been at the store sometime prior to this robbery?
      • To plan this robbery and execute it with this level of precision, it is very likely that the suspects spent at least some time looking over the premises and the surrounding area to plan their approach, execute the robbery, and plan their escape.
    5. What relevant theories might be considered from the way the suspects were dressed?
      • It appears that all three suspects were wearing similar outfits with dark jackets, blue jeans, and ski masks. This may indicate that the suspects deliberately purchased specific gear for committing a crime.
      • This clothing might be considered somewhat non-descript, and not easily distinguishable or unique for a witness to accurately or specifically describe the fleeing suspects. The use of masks and non-descript outfits might indicate that the criminals were experienced.
      • The fact that they are all wearing jackets on a summer day in August might indicate that they were covering up tattoos, scars, or other distinguishing features that might otherwise assist in identifying the suspects.
      • The fact that all suspects were wearing gloves would indicate that they are aware that any fingerprints left behind could identify them.
    6. What relevant theories might be made from handguns being carried by the robbers?
      • Handguns are more easily concealed and may be the weapon of choice for more professional criminals. Handguns are more difficult to obtain, and legal handguns are generally registered, so it is likely that these were unregistered or stolen handguns.
    7. What might be theorized from the way they carried out the robbery?
      • From the overall planning and precision in the execution of the robbery, it might be theorized that this is not the first robbery that these three have done together. This method may have been used elsewhere.
    8. What might be theorized considering the items taken?
      • Considering that the items taken were specialty items and that some were marked with identifying serial numbers, it might be theorized that the robbers have a prearranged or preplanned means of disposing of the items or otherwise converting them to cash.
    9. Were these three suspects working alone?

    This page titled 13.1: ROBBERY INVESTIGATION was last modified on Fri, 28 Aug 2026 21:21:36 GMT and is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by George Cartwright.