Table 1.

Key variables involved in creating a geographic profile for clandestine grave searches.

Intelligence type	Information collected	Importance
Case-specific information	when/where victim(s) was last seen, and the clothing/personal items they were seen in [45]	This information can be used to highlight the activity spaces of both the offender and the victim(s), i.e., where they spent most of their time. It can also demonstrate where the offender and victim could've interacted.
	residences and workplaces of offender and victim(s)
	locations the offender and victim(s) frequented
	telephone records and triangulation of telephone connections [46]
	witness statements
	types of vehicles that the offender has access to [28,46,47]
Spatial	potential routes taken to and from points of interest [48]	Once the offender's activity space is mapped out, spatial patterns can be highlighted and analysed. By mapping out the distance between anchor points, the potential routes taken to and from points of interest, highlighting physical and mental barriers, and the offender's awareness space, possible body deposition sites can emerge. Areas that are discrete yet accessible may be desirable [46,49], especially if the area is known (and potentially meaningful) to the offender [11]. More specifically, research has shown that body deposition sites are approximately 15 km from an anchor point, but can be further if the offender has a personal relationship with the victim, and will be 2–3 m away from a road [23].
	distance between anchor points and points of interest
	physical and mental barriers such as highways and rivers
	areas nearby that are discrete, yet accessible [49]
	offender's awareness space (area just outside activity space)
Temporal	time of year, month, week, and day [29]	Time is an important aspect because criminal activity may be more feasible at different times. For example, time of the year is particularly important for places that cycle through periods of extreme seasons, namely winter, as using a clandestine grave for body deposition may not be possible as the ground in some places freezes. Based on an offender's work schedule, certain times of the month or week may be more likely due to pay days and days off. For time of day, although depositing a body at night may provide more protection from being witnessed, depositing a body during the day is easier. The time since the victim(s) disappearance is important, especially in cold cases, because the environment will have more time to change. Lastly, the amount of time that the offender spends with the victim(s) is important because spending an increased amount of time with them may mean that there is more time that needs to be accounted for when questioned. That amount of time can dictate how far out from an offender's anchor points the victim could be buried.
	time since the victim(s) disappearance
	amount of time that the offender spent with the victim(s)
Environmental	geomorphological information such as soil colour, soil depressions or mounds, lack of plant growth, or change in the dominant plant species [10,15,[50], [51], [52], [53]]	The act of digging a grave will permanently disturb the soil strata, resulting in soil colour changes and mounds/depressions [10]. Digging a grave will also disrupt the surrounding plant environments, resulting in a complete lack of plant growth or increased growth, or if enough time has passed, a change in dominant species [53]. These geomorphological changes can indicate potential areas with clandestine graves.
Geographic	natural formations	Each of the spatial, temporal, and environmental aspects are influenced by the underlying geography, however, there are also strictly geographic aspects, such as natural formations, that can influence criminal behaviour. There is also human-made infrastructure (often dependant on natural formations) such as walls, buildings, and lighting that can make certain areas attractive to a criminal [54].
	human-made infrastructure [54]
Offender profile	offender demographics, employment history, social interests, and personality [47]	Understanding the offender, including their motivations, personality, and potential personality or mental health conditions can indicate what type of offender they are and can highlight potential body deposition sites [55]. Understanding whether the offender is organized or disorganized, or if they have any mental health or personality disorders, will be suggestive of the amount of premeditation and thus detection avoidance [7,23]. Contrarily, there could be an element of impulsivity, meaning that the resulting deposition site will be chosen in haste and may therefore lack meaning to the offender.
	organised/disorganized offender [55]
	offender motivations [47]
	diagnostic evaluations and offender characteristics [55]
	how the offender identifies with the crime
Victimology	victim demographics	Victim demographics are important, especially for serial offenders, as they often select similar types of victim [56,57]. The relationship between the victim and offender, and how the offender identifies with the victim, can be telling of potential deposition sites as well. For example, offenders who feel no remorse for their victims may be deposited in places that mirror this, such as a rubbish tip (see the Mr. Cruel case for an example of this [44]), whereas if the offender feels remorseful, the victim may be buried close to or on the property of an anchor point (see the Christopher Watts case for an example of this [58])
	financial situation [59]
	relationship status and family issues [59]
	Business or personal concerns or pressures, including health and lifestyle choices [59]
	relationship between victim and offender [47]
	how offender identifies with the victim