Recent high-profile criminal cases such as the suspicious death of William Tyrell and the kidnapping of Chloe Smith have attracted media and public attention.
As a former detective inspector, I have investigated and managed more than 25 murder investigations and many other major crimes over the course of 28 years with the Queensland Police Service.
So what happens behind the scenes in a major crime investigation. And how does the investigation of a major crime differ from a volume crime?
Difference Between Major Offense and Quantitative Offense
Murders are the most obvious type of major crime, but can also include organized crime such as robbery, rape and other serious crimes.
The Queensland Crime and Corruption Commission’s list of major felony offenses includes drug trafficking, fraud, money laundering, criminal pedophilia and murder.
The Australian Institute of Criminology Volume defines crime as crimes that account for the largest proportion of crime recorded by the police. These include illegal entry, assault, motor vehicle theft and theft.
There is a difference in the method of investigation of a large crime and a large scale crime. Major crime investigations can take years for some cases, such as the murder of 13-year-old Daniel Morcombe, which took 11 years to reach conviction.
In a larger crime, there is a clear division of labor, with only one officer doing everything, as is usually the case with large-scale crime investigations. Assigned roles include investigation manager, arrest team, other investigators, an intelligence cell and specialist support staff.
Major crimes such as murders involve dedicated workforces or operations consisting of large teams of detectives who conduct parallel lines of investigation.
Typically, a major event room is set up.
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Clear rates for major crimes
This ability to provide greater investigative effort and expert support in major crime investigations contributes to the very high “clear-rate” for these types of crimes – when a suspect is identified and proceedings are initiated.
A study from New South Wales showed that, from 2007 to 2016, police had sanctioned 65% of murders within 90 days. The same study noted that the apparent rate was much lower for property crimes than for violent crimes, including murder. In Queensland, 96% of recorded murders in 2019-20 were sanctioned.
Australia’s approval rate for murder is well compared to the rest of the world. The United Nations Global Study on Murder indicates that the evacuation rate is between 50% and 90%.
hunting for information
Most major investigations are a process of moving from knowing little about a crime to having a lot. It is essentially an exercise in information management. Investigators need to gain information in order to make a practical account of what has happened.
Investigators do this by identifying, interpreting, and combining information that shows whether a crime has been committed, and who is responsible for that crime. Sources of information can include crime scene material, intelligence databases, witnesses, victims and the media.
an investigative model
There is no standardized testing procedure or model. The United Nations Office of Drugs and Crime provides some guidance on how to progress through a general reactive investigation in its crime investigation toolkit.
In the United Kingdom, the College of Policing provides guidance on the investigation process. However, it notes that each investigation is different, and therefore a different approach may be needed to resolve the matter.
In 2001, as part of a research project in collaboration with the Queensland Police Service, I developed an investigative model. It outlined several steps:
- crime scene
- initial assessment
- to arrest.
During the course of the investigation, the police can return at any stage and start a new line of investigation. We’ve seen this happen with the disappearance of William Tyrell, the police returning to the original crime scene after seven years of new information.
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No matter which model is used, there are decisions that the management team of an investigation will need to make as they go through the stages:
knowledge judgment Concerned about how specific information should be interpreted and treated by the investigative team
strategic decision relating to what, when and by whom it should be done
logical judgment Concern operational support and resources to be devoted to an investigation
legal decision This needs to be done to ensure that any action taken by the investigative team is legal and admissible in a court case.
Role of media and technology
The media is a great investigative tool and can be used to exert strategic pressure on suspects and seek information from the public. The widespread coverage of high-profile cases, such as those of William Tyrell, is an example. The use of media can also coincide with covert policing strategies, such as listening devices, designed to target potential suspects.
Technology still plays a huge role in major investigations. We all leave a digital footprint, whether they are passive (your mobile phone searching for a signal from a cell tower) or active (using your phone to pay for fuel at a geographic location).
In a triple-murder investigation that I managed, criminals were tracked using their mobile phone data, up and down Australia’s eastern coastline, and to murder scenes.
One thing that hasn’t changed over time is the importance of investigative efforts in the early stages of any major crime, but murders in particular. I have seen firsthand how a large crime can be solved by rushing the effort in the long run and in terms of sufficient resources.