In the following article BCL’s partner Shaul Brazil examines the application in the United Kingdom of the ‘forum bar’ to extradition which was introduced following widespread criticism of the perceived imbalance in the extradition arrangements between the United Kingdom and the United States and the so-called ‘long arm’ jurisdiction of United States criminal law.

Extradition relations between the United Kingdom and the United States have a long history. They began in 1794 and over the next 200 years the two countries entered into five substantive treaties on extradition. Most recently, on 31 March 2003, the Treaty on Extradition between the Government of the United States and the Government of the United Kingdom was signed (but ratified by the United States only in 2006).

It is, however, no exaggeration to say that the 2003 Treaty has proved to be significantly controversial. Since the 2006 case of the ‘NatWest 3’ (whose extradition from the United Kingdom was sought in connection with the collapse of Enron) there has in the United Kingdom been regular and frequent criticism (both public and parliamentary) of a perceived asymmetry in the evidential burden required by each party.

The 2003 Treaty removed, under Article 8, the requirement on the United States to supply prima facie evidence. Conversely, the United Kingdom must provide ‘such information as would provide a reasonable basis to believe that the person sought committed the offence for which extradition is requested.’

Arguably, however, the effects of this apparent imbalance are not quite so profound as many observers believe. It would likely be a rare case that the United States, having obtained a grand jury indictment, could not validate an extradition request to the United Kingdom by providing sufficient information to substantiate a reasonable basis to believe that an offence had been committed. Rather, the true reason for the criticism of the arrangements lies with the far-reaching extraterritorial scope of United States criminal law.

In the years following the 2003 Treaty there have been numerous examples of requests made by the United States for the extradition of individuals from the United Kingdom in circumstances where many observers considered the conduct alleged ought properly to have been the subject of proceedings in the United Kingdom. That was the primary criticism in the case of the ‘NatWest 3’ and it was the concern expressed at the time of various subsequent cases.

The matter came to a head in 2012 following the English courts’ decision to extradite Gary McKinnon, an alleged hacker who had accessed US government computers but claimed that he was looking for evidence of UFOs. Mr McKinnon suffered from Asperger’s syndrome and depressive illness such that his extradition was ultimately blocked by the then Secretary of State, Theresa May. This led in 2013 to the introduction in the United Kingdom of the ‘forum bar’.

The forum bar operates to prevent extradition in cases where ‘a substantial measure’ of the requested person’s conduct took place in the United Kingdom and the court finds that extradition would not be in the interests of justice, having regard to an exhaustive list of statutory considerations. Those considerations include: the place where most of the harm or loss occurred; the interests of victims; the most practical jurisdiction for a prosecution to take place, taking into account the location and availability of evidence; any belief of the prosecutor that the United Kingdom is not the most appropriate jurisdiction; and the defendant’s connections with the United Kingdom.

In practice, however, the application of the forum bar in any individual case is hard to predict. For the first few years after its introduction, all forum defences were refused. It was not until 2017 that the United Kingdom’s High Court finally allowed an appeal on forum grounds in the case of Lauri Love, another alleged computer hacker who suffered from Asperger’s Syndrome and was particularly vulnerable.

Some commentators predicted that Mr Love’s case would be a one-off, but the High Court proved them wrong the following year in the case of Stuart Scott, an HSBC foreign exchange trader who was wanted for defrauding his corporate client in relation to a $3.5 billion dollar-sterling transaction which he was accused of front running. Mr Scott was therefore the first white collar defendant to successfully defend extradition to the United States on forum grounds.

Mr Scott was successful primarily on the basis that the victim was a United Kingdom-based company (which had suffered the only quantified harm identified in the case), combined with his strong connections to the United Kingdom. This was despite the fact that the United Kingdom authorities (the SFO) had during the extradition proceedings confirmed to the court that they had no intention of prosecuting Mr Scott. As such, whilst there was a theoretical possibility that the SFO might change