The Concept of Leakage in Threat Assessment

Abstract

Leakage in the context of threat assessment is the communication to a third party of an intent to do harm to a target. Third parties are usually other people, but the means of communication vary, and include letters, diaries, journals, blogs, videos on the internet, emails, voice mails, and other social media forms of transmission. Leakage is a type of warning behavior that typically infers a preoccupation with the target, and may signal the research, planning, and implementation of an attack. Nomothetic data suggest that leakage occurs in a majority of cases of attacks on and assassinations of public figures, adult mass murders, adolescent mass murders, and school or campus shootings: very low-frequency, but catastrophic acts of intended and targeted violence. Idiographic or case data illustrate the various permutations of leakage. We discuss the operational importance of the concept, place it in the context of other warning behaviors, emphasize the need for further research, and outline risk management strategies for the mitigation of such acts of violence in both law enforcement and clinical mental health settings.

Lone Actor Terrorist Attack Planning and Preparation: A Data‐Driven Analysis,

“…Operational security includes behaviors that lone actors deliberately engage in to minimize their chances of detection while planning or preparing an attack. Leakage behavior, as defined by Meloy and O'Toole, refers to the behavior of (would‐be) lone actors who intentionally or unintentionally divulge their motivation or capability to commit acts of violence, thus providing opportunities for early detection and intervention .…”

Same but Different? Developmental Pathways to Demonstrative Targeted Attacks — Qualitative Case Analyses of Adolescent and Young Adult Perpetrators of Targeted School Attacks and Jihadi Terrorist Attacks in Germany

“…The existing research on both school shootings and terrorism indicates that the perpetrator’s redefinition of self from victim to self-perceived avenger is associated with self-empowerment for violent action. The perpetrator increasingly moves into a phase of clandestine planning characterized by a state of tension between secret private rituals and public intimation (leakage) (Gill, 2015; Meloy & O’Toole, 2011; Meloy, Mohandie, Knoll, & Hoffmann, 2015). Many investigators have been able to reconstruct different trigger events after which the perpetrator might view the act of violence as necessary, justified, inevitable, and meaningful (Corner & Gill, 2015; Heitmeyer, Böckler, & Seeger 2013; Meloy & Gill, 2016).…”

“…Alongside secret planning and private rituals, the new self-concept is also expressed outwardly and reflected in visibly altered behavior, for which the term leakage (also leaking) has become established (Meloy & O’Toole, 2011; O’Toole, 1999; cf. Bondü & Scheithauer, 2014b).…”

The Concept of Identification in Threat Assessment

“…Identification, and its observable correlates, has emerged as one important warning behavior in threat assessment for targeted or intended violence (Meloy, ; Meloy & O'Toole, ; Meloy, Hoffmann, Guldimann, & James, ; Meloy, Hoffmann, Roshdi, Glaz‐Ocik, & Guldimann, 2014). It has been identified as one of eight superordinate patterns of warning behaviors, which may indicate dynamic and accelerating risk of targeted violence across a variety of domains, such as school shootings, mass murder, public figure attacks and assassinations, and terrorist acts.…”