Between 2007 and 2015, Darin served as a Federal Bureau of Information intelligence analyst for the Omaha Division. He regularly wrote intelligence reports used for decision makers, including several used for briefings to the President of the United States (POTUS). He has provide intelligence briefings to admirals, generals, governors, police chiefs, sheriffs, US attorneys, and CEOs, including a monthly briefing to the State of Iowa’s governor and lieutenant governor.
Darin was recognized with several FBI and FBI Omaha-specific awards, several Iowa-specific awards, and an award for collaboration given by the DNI in 2015.
While at the FBI, he completed over a hundred training courses on a variety of national security, intelligence, and law enforcement topics. He was certified as Chief Reports Officer (awarded by FBI in 2015). Darin also completed the prestigious Intelligence Community Advanced Analyst Program (ICAAP), which was awarded by the DNI in 2015. The ICAAP represents completion of ten advanced-level intelligence analysis courses. He has trained at the CIA’s Sherman Kent School and the DIA Joint Military Intelligence Training Center (JMITC).
In 2017, Darin worked on a Department of Homeland Security contract on the topic of countering violent extremism for the greater Kansas City area.
Since 2017, Darin is involved in research on the domestic movement sovereign citizens. He regularly publishes blog postings about the movement. He has been interviewed several times for podcasts, and he has published the following research-based publications on this topic:
Challacombe, D.J. (In press). A tale of six people: Using the TRAP-18 to analyze the U.S. Capitol insurrection participants. In M. Herzog-Evans & S. Morewitz (Eds.), Handbook of Understanding Terrorism: Forensic social sciences case studies (Chp. 9). ISBN: 978-3-031-67790-8.
Challacombe, D.J. (2022). Review of “Religiously motivated terrorism: A systematic review exploring causal pathways”. Qeios.
Challacombe, D.J. (2022). Synergy between cults and terror groups: A systematic review of recruitment processes. International Journal of Coercion, Abuse, and Manipulation. doi:10.54208/1000/0003/005
Challacombe, D.J., & Lucas, P. A. (2018). Postdicting violence with sovereign citizen actors: An exploratory test of the TRAP-18. Journal of Threat Assessment and Management. 6(1), 51–59. doi:10.1037/tam0000105
Challacombe, D.J., & Patrick, C.L. (2022). The January 6th insurrection at the U.S. Capitol: What the TRAP-18 can tell us about the Participants. Journal of Threat Assessment and Management. doi:10.1037/tam0000194
Vargen, L., & Challacombe, D.J. (2023). Violence risk assessment of Sovereign Citizens: An exploratory examination of the HCR-20 Version 3 and the TRAP-18. Behavioral Sciences & The Law. doi:10.1002/bsl.2607