“Killing All Infidels”: Leaking Prior to Islamist Terrorist Attacks in Germany

ABSTRACT

Leaking includes observable statements, offense-related behaviors, and an interest in similar offenses prior to severe targeted violence, making it a crucial starting point for the prevention of Islamist attacks. Most studies to date only examined the frequency of leaking, used a narrow definition, and based on open source data. Thus, little is known about its contents, trajectories, and assessment criteria. We analyzed the prosecution files of 27 Islamist attacks in Germany (48 offenders) and of 52 individuals that showed leaking, but did not execute an attack (comparison group). Leaking was shown by 96 percent of the offenders, often repeatedly and over an average period of one year. Most leaked face-to-face, via observable behavior, or in chats. Leakings rarely included details of the planned attack, but rather signaled an interest in similar attacks/terrorism and the preparation of an attack. Over time, leaking became more closely offense-related, indicating a pathway to an attack. Leaking differed significantly between offenders and the comparison group in contents and characteristics that were combined into the risk assessment tool LATERAN-IT that assesses the seriousness of Islamist-motivated leaking. Hence, leaking allows for the identification of potential Islamist terrorists in advance, so that law enforcement authorities can prevent future attacks.

KEYWORDS:

• Leaking
• Islamist terrorism
• risk assessment
• warning signs
• LATERAN-IT

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical approval

Approval was obtained from the ethics committee of Psychologische Hochschule Berlin.

Due to the sensitive nature of the research, supporting data is not available for ethical and legal reasons.

Notes

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61. Rose and Morrison, “An Exploratory Analysis of Leakage.”

62. Ibid.

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66. See note 8 above.

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68. Bondü and Scheithauer, “Kill One or Kill Them All?”

69. See note 36 above.

70. See note 8 above.

71. See note 7 above.

72. See note 65 above.

73. L. Tampe and R. Bondü, LATERAN-IT: Evaluation eines Instruments zur Einschätzung der Ernsthaftigkeit von Ankündigungen islamistisch motivierter terroristischer Taten [LATERAN-IT: Evaluation of an instrument for assessing the seriousness of announcements of Islamist-motivated terrorist attacks] (Manuscript in preparation).

Additional information

Funding

This research was funded by the German Ministry of Education and Research (Bundesministerium für Bildung und Forschung), Grant No. [13N14885].

Notes on contributors

Laura Tampe

Laura Tampe is a PhD student in psychology at Psychologische Hochschule Berlin. Her research interests include risk factors for aggressive behavior, warning signs of severe violence, possibilities of prevention, as well as threat and risk assessment.

Rebecca Bondü

Rebecca Bondü earned her Ph.D. in Psychology and is a Professor for Development, Education, and Family Psychology at Psychologische Hochschule Berlin. Her research focuses on risk and protective factors for prosocial and aggressive behavior and comprises topics such as warning signs for severe violence, aggressive (sexual) fantasies, as well as sensitivity to injustice and rejection.