By Emily Mandel

bSci21 Contributing Writer

A pilot study conducted by James Hughes in 2009 investigated the use of behavior analytic methodology in hostage negotiation. A hostage negotiation, as defined by The Negotiation Experts, is “a negotiation conducted between law enforcement agencies, diplomatic or other government representatives for the release of a person(s) held hostage against their will by criminal, terrorist or other elements” (“Hostage Negotiation.” Retrieved November 28 from, from http://www.negotiations.com/definition/hostage-negotiation).

In the Hughes study, audiotapes from 3 hostage negotiations were analyzed with specific focus on hostage negotiators’ use of behavioral momentum, or high-probability request sequences, in gaining compliance from hostage-takers. Behavioral momentum “refers to the tendency for behavior to persist following a change in environmental conditions. The greater the rate of reinforcement, the greater the behavioral momentum” (Mace et al., 1988). Behavioral momentum consists of a presentation of a sequence of requests with which an individual is likely to comply (high-probability requests) followed by the presentation of a request with which an individual is less likely to comply (a low-probability request). The momentum with which the individual complies with a sequence of high probability requests increases the likelihood that he or she will comply with a subsequent low probability request. The 3 hostage negotiations highlighted in the Hughes study were a 1972 robbery attempt in Brooklyn, a 1991 robbery attempt in Sacramento, and a 1981 invasion of FBI offices in Atlanta.

In the 2009 Hughes study, a total of 617 requests were made by hostage negotiators across all 3 scenarios. These requests were placed into 4 categories. Category 1 consisted of requests for non-personal information, clarification questions, and questions regarding situational information. Category 2 consisted of requests for personal information, which included thoughts, feelings, and personal identification. Category 3 consisted of requests to engage in various behaviors that did not include forfeiting negotiating items. Category 4 consisted of requests to surrender negotiating items such as hostages or weapons.

In the 1972 robbery attempt in Brooklyn, the hostage-taker complied with 77% of Category 1 requests, 47% of Category 2 requests, 33% of Category 3 requests, and 9% of Category 4 requests. The first instance of compliance with a Category 4 request resulted in 1 of the 3 hostages being released, and was preceded by compliance with a sequence of 3 high-probability requests. The second instance of compliance with a low-probability request (hostage-taker surrendering himself) was preceded by compliance with a sequence of 9 high-probability requests. The hostage-taker did not comply with any of the low-probability requests that were preceded by a sequence of fewer than 3 high-probability requests.

In the 1991 robbery attempt in Sacramento, hostage-takers complied with 58% of Category 1 requests, 53% of Category 2 requests, 43% of Category 3 requests, and 2% of Category 4 requests. Hostage-takers only complied with 1 low-probability request (the release of one hostage), which was preceded by 9 high-probability requests. There was 0% compliance with the 40 low-probability requests that were preceded by fewer than 3 high-probability requests. The hostage situation in Sacramento ended violently, with 14 hostages injured, 3 hostages killed, and 3 of the 4 hostage-takers killed.

In the 1981 invasion of FBI offices in Atlanta, the hostage-taker complied with 93% of Category 1 requests, 62% of Category 2 requests, 90% of Category 3 requests, and 14% of Category 4 requests. The hostage-taker was compliant with 1 low-probability request (the release of 3 hostages), which was preceded by a sequence of 5 high-probability requests. The hostage-taker did not comply with the 5 low-probability requests that were preceded by fewer than 3 high-probability requests. The hostage negotiation in Atlanta resulted in the hostage-taker being shot and killed.

Hostage-takers complied with only 4 of the 70 combined low-probability requests in these 3 hostage negotiation situations. The low-probability requests with which the hostage-takers complied were all preceded by a sequence of 3 or more high-probability requests, suggesting that the greater the number of high-probability requests within the sequence, the likelier the individual was to comply with subsequent low-probability requests. For low-probability requests preceded by 3 or more high-probability requests, conditional probability was .8 (compliance in 4 out of 5 opportunities).

There were several limitations to the study. First, the there were several instances of poor audiotape quality, so several clips could not be scored. Second, the transcription of the audiotapes did not take into account the elapsed time between verbal exchanges. The final limitation was that only 3 hostage negotiations were analyzed, with a combined compliance with only 4 low-probability requests. Of these 3 negotiations, 2 ended violently before hostage negotiators could make more requests. Future research should continue to investigate the effectiveness of high-probability request sequences in hostage negotiation. Specifically, researchers should aim to identify the optimal number of high-probability requests to evoke compliance with subsequent low-probability requests.

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Hughes, J. (2009). A pilot study of naturally occurring high-probability request sequences in hostage negotiations. Journal of Applied Behavior Analysis, 42(2), 491-496. doi: 10.1901/jaba.2009.42-491

Mace, F.C., Hock, M.L., Lalli, J.S., West, B.J., Belfiore, P., Pinter, E., & Brown, D.K. (1988). Behavioral momentum in the treatment of noncompliance. Journal of Applied Behavior Analysis, 21(2), 123-141. doi: 10.1901/jaba.1988.21-123

Emily Mandel, M.S., BCBA, is a behavior clinician who works with children on the Autism Spectrum in the Greater Boston Area. She has over 3 years of experience delivering therapeutic services both in-home and in the public school system. Though she is predominantly focused on the utilization of Applied Behavior Analysis in treating individuals with disabilities, Emily enjoys examining topics such as religion, medicine, politics, and social constructs, through a behavioral lens. You can contact her at emandel90@gmail.com.