Forum Bar

Section 19B of the Extradition Act 2003 provides that "the extradition of a person ('D') to a category 1 territory is barred by reason of forum if the extradition would not be in the interests of justice." This is not a bar simply because some UK conduct is involved: the extradition will only fail on this ground where the judge "decides that a substantial measure of D's relevant activity was performed in the United Kingdom" and, having weighed the specified matters relating to the interests of justice, "decides, having regard to the specified matters relating to the interests of justice (and only those matters), that the extradition should not take place." The specified matters (set out in the remainder of the section) include the place where most harm resulting from the conduct occurred, the interests of victims, any belief of a prosecutor that the UK is not the most appropriate jurisdiction, and the desirability of not requiring disclosure of material restricted in the requesting territory.

The forum bar was inserted into the 2003 Act to address concern, following high-profile cases, that individuals with substantial UK connections to alleged offending could be extradited to a category 1 (European) territory without a UK prosecutor first having considered domestic prosecution. Where a prosecutor certifies that they have considered prosecuting the person in the UK for the same conduct, the prosecutor becomes a party to the forum-bar proceedings, giving them standing to make submissions on why extradition should nonetheless proceed.