Stalking is a significant social issue. The inconsistency as to what defines stalking has resulted in the creation of different methods to measure the crime. The aim of the present study was to assess the level of stalking behavior in terms of severity within a randomly selected sample of 924 cases from the database of the National Stalking Helpline. Item response theory analyses is a statistical process that provides for the design, analysis, and scoring of tests, questionnaires, and similar instruments measuring abilities, attitudes, or other variables. It is a theory of testing based on the relationship between individuals' performances on a test item and the test takers' levels of performance on an overall measure. In the case of this study, the analysis was used to assist in developing a scale that displays the ranking order of each stalking behavior. These analyses were also used to examine whether the stalking behavioral items created a single continuum of severity of stalking.

A body of research examining stalking has focused on perpetrators’ tactics, (in other words, the stalking behaviors that perpetrators used on their victims). Although a victim’s stalking experience is unique, and the motivations of stalkers vary significantly, the methods or tactics employed by stalkers share the same underlying characteristics (White et al., 2020). Compared to males, females experienced significantly longer duration of many unwanted behaviors (Chan et al., 2020). Overall, studies indicate that, in most cases, stalking is a crime of surveillance and unwanted communication. However, in some cases, stalking behaviors are acts that foreshadow serious violence or homicide (James & Farnham, 2003; Miller, 2012).

Research also shows that while some stalking behavior is very severe, even stalking behaviors which are considered as lower severity by the criminal justice system may hide or lead to severe behaviors given that these nonphysical stalking behaviors may escalate to more serious acts. Stalking comprises a variety of behaviors, including domestic violence, sexual assault, and homicide (Purcell et al., 2004). Norris et al. (2011) and Logan, Shannon, & Cole (2007) note that there is a strong relationship between domestic violence and stalking, as stalking occurs more frequently between ex-intimates. Additionally, research suggests that ex-intimate-stalking is the most pernicious and violent form of stalking (Kamphuis et al., 2003; White et al., 2020).

Results from this study indicated that 16 stalking behavioral items of the 28 items present in the National Stalking Helpline, best represented the severity of stalking. Unwanted communication behaviors such as text messages and phone calls were located at the lower end of the severity scale, whereas criminal damage and death threats were mapped on the higher end of the continuum. The findings also revealed that the 16 items categorized under 6 factors.

(The expanded abstract is excerpted and adapted from the article cited above)