Started Sep 11, 2020 05:00PM UTC   •   Closed Sep 01, 2021 07:01AM UTC

Private Superforecasting Workshop asks:

Will there be a complex coordinated terrorist attack (CCTA) in the United States before 1 September 2021?

CCTAs are a major concern for law enforcement and emergency planners (FEMA). For the purposes of this question, a CCTA is an [1] act of terrorism [2] involving multiple perpetrators working in concert [3] initiated with little or no warning [4] and employing one or more weapon systems (e.g., firearms, explosives, fire as a weapon, poison gas) [5] that is intended to result in large numbers of casualties. For the purposes of this question, "terrorism" is as defined by federal law in 18 U.S.C. § 2331(5) (Cornell). Examples of CCTAs include the 2004 Madrid train bombings, the 2008 Mumbai attacks, 2013 Boston Marathon bombings, and the 2015 San Bernardino, CA, office attack.

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The question closed "No" with a closing date of 1 September 2021. As of the resolution of this question, available evidence does not support any incident during the question's open period, including the 6 January 2021 Capitol riots, as having met all five elements that constitute a CCTA. Particularly, currently available reporting related to the 6 January 2021 Capitol riots indicates that these events met four out of five criteria needed for a CCTA.

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