Violent Attacks on Public Surface Transportation and Commercial Aviation

While few in number, attacks by mentally disordered persons on surface and air transportation can be lethal and pose special security challenges. MTI’s latest Transportation Security Perspective, The Threat to Air and Ground Transportation Posed by Mentally Disordered Assailants, authored by Brian Michael Jenkins, director of MTI’s National Transportation Safety and Security Center, and MTI Research Associate Bruce Butterworth, reviews violent attacks on public surface transportation and commercial aviation to explore the nature of the threat posed by mentally disordered assailants.

The analysis is based on the Mineta Transportation Institute’s database of 5,047 attacks on public surface transportation since 1970 and a separate database compiling 132 attacks against scheduled airliners serving the public and commercial airports since 9/11.

Of the 5,047 attacks on public surface transportation, 53 (1 percent) were perpetrated by attackers categorized as mentally disordered. Despite the small number, there does appear to be a trend showing an increase in the number of attacks, particularly since 2000, and they also appear to be growing more lethal. Conversely, since 9/11, there have been 132 attacks against aviation targets, including commercial airports; 15 (11 percent) of these have involved mentally disordered persons as categorized by the authors. 

There is understandable concern among mental health professionals about stigmatizing the mentally ill, who are often incorrectly portrayed as violent. As Jenkins’ noted, “the mentally disordered do not represent a significant threat to society or to public transportation. More mentally stable actors with ideological motives pose a far greater threat.”