A Department of Homeland Security Center of Excellence led by the University of Maryland

Communicating Risk of Mass Casualty Terrorism in Diverse Communities

Communicating Risk of Mass Casualty Terrorism in Diverse Communities


Project Details


This series of studies of risk perceptions and risk communication involved members of diverse groups within the population, such as members of racial and ethnic minority groups, lower-income inner-city residents, non-English speakers, and elderly persons, with the objective of gaining a better understanding of their emotions, perceptions, comprehension, and decision-making with respect to homeland security threats. Based on empirical evidence, the project provided recommendations about information sharing and communications that impact preparedness and resilience regarding homeland security threats within lower-income communities and among other groups residing in densely populated, culturally diverse urban areas (locations more likely to be the focus of those interested in carrying out acts of mass-casualty terrorism). The original empirical studies generated new knowledge and understanding of heterogeneity among populations in reasoning strategies, evaluation of threat or risk information, emotions, risk perceptions, behaviors and response to risk communications about homeland security threats.

Primary Findings: 

Well-documented communication challenges often emerge within certain ethnic, socioeconomic and cultural groups in the U.S. during extreme risk events including: uneven communication effectiveness, increased difficulties in maintaining public trust and greater likelihood of unintentional and "surprising" negative consequences of risk communications. This research yielded insights on bioterrorism crisis communication in diverse urban populations:

  • Certain communication errors are extremely significant for public trust during an unfolding terrorism incident. Within some lower-income African-American and Hispanic communities, in the short term, "false negative" errors (premature reassurances) can severely damage the credibility of homeland security officials much more than "false positives" (warnings that never materialize). "False negative" errors seem to violate cultural expectations or "norms" regarding what values should guide risk management and communication. Effects can persist, biasing subsequent message interpretations, eroding trust and affecting what information is ignored or amplified.
  • For early stages of terrorism events, individuals expect and can accept uncertainties and disturbing information in messages. However, trust is threatened if communications delay acknowledgement of uncertainty and fail to reference important cultural values (e.g., protect the most vulnerable).
  • Some individuals display a strong tendency for "precautionary thinking" to evaluate homeland security decisions. This orientation is associated with a deep distrust of government, greater "monitoring" for message inconsistencies, skepticism about recommended protective actions and reluctance to accept the "surface" meaning of crisis communications. Statements intended to reassure (e.g., "Stay calm," or "There's no need to worry at this time") can be re-interpreted as a "signal" that information is being withheld, and unexpectedly increase fear. Effects can be attenuated through repeated communications that openly acknowledge community priorities and distrust.
  • Correcting missteps in crisis communication is more difficult within certain cultural and social contexts. This is significant because initial crisis communications during a developing extreme event will contain errors and gaps. During the 2001 anthrax attacks, early statements from homeland security officials reflected some good practices, but key mistakes also were evident. As the crisis progressed, errors were less prevalent, but consequences of initial missteps may persist in some communities.

This research utilized a multi-method approach. Characteristics of official crisis communications that appeared in news broadcasts as the 2001 anthrax bioterrorism episode unfolded were examined with qualitative data analysis software for video files. Archival research identified relevant news broadcasts between October 4, 2001 and August 15, 2002 from the Vanderbilt University TV News Archives. Vanderbilt compiled a chronological video record of a sample of these broadcasts and transferred this to several DVDs for analysis and use in subsequent stages of the research. Bioterrorism risk perceptions and responses to changing crisis communications were explored in several ethnically and culturally diverse communities in high priority urban areas in Southern California (i.e., near sites more likely to be targeted by terrorists). Initial research completed extensive literature reviews, focus groups and individual semi-structured interviews. Qualitative data analysis techniques identified relationships between cultural and socioeconomic background, and themes regarding bioterrorism crisis communication. Findings informed the development of culturally appropriate survey instruments measuring precautionary value orientations toward risk and uncertainty, trust in government agencies' capacity for effective bioterrorism response and perceptions of government authority to implement actions that could restrict personal freedoms during an extreme terrorism event. Instruments were subsequently validated in a quantitative measurement study with independent samples.


Project Period: 
May 2005 to May 2009