pressure cooker bomb
Improvised explosive device using a household pressure cooker as fragmentation shell
A pressure cooker bomb is, in a US context, an improvised explosive device in which an ordinary household pressure cooker is used as the container for an explosive charge. The term is a technical and descriptive label for a particular construction principle and does not appear as an independent legal category in any specific federal statutory provision.
At the Boston Marathon bombing on 15 April 2013, two such devices detonated near the finish line on Boylston Street. The FBI and other official US authorities subsequently described the bombs as pressure cookers packed with explosives together with metal fragments in the form of nails and ball bearings. The design is intended to make the pressure cooker's metal casing act as a fragmentation shell that is dispersed at high velocity on detonation, markedly increasing the destructive effect.
In US federal criminal law, such devices are treated legally under the broader categories of 'destructive device' or improvised explosive devices. It is these overarching designations that form the basis for charges and conviction, while the expression pressure cooker bomb functions primarily as an operational and evidentiary descriptive term in indictments, court documents and agency reports.
Dzhokhar Tsarnaev, who was sentenced to death in 2015, and his deceased brother Tamerlan Tsarnaev were behind the bombing. The construction of the devices used formed central evidence in the case and was documented in detail by the FBI as part of the investigation into the terrorist attack, which killed three people and injured more than 260.
