Dealing With Cases Involving Joint USA and UK Investigations

Large scale police investigations now invariably involve joint cooperation with countries inside the EU.  Mutual cooperation within the EU is relatively commonplace and underpins the very nature of the European Union.  If we leave the EU the position post Brexit remains unclear.  But what about UK/USA investigations? Steve Nikolich explores the issues.

Steve Nikolich

The position with the UK and the USA would appear to remain unchanged post-Brexit and our main concerns as lawyers operating in England & Wales, remains focused on how our two countries deal with extradition and how they cooperate with Investigations. This article intends only to deal with the generality of such broad issues and outline the essential legal frameworks currently involved.

Extradition to/from the USA

The Extradition Act 2003

The Extradition Treaty of 2003

The current test in UK law requires ‘reasonable cause’ to extradite from the US to the UK.  Whereas the US test is simply one of ‘probable cause’ reduced from ‘prima facie case’ in the 2003 Act, to extradite someone from the UK to the US. Arguably therefore it is now easier for the US than before. The Commons Home Affairs Select Committee has said that British people were losing confidence in the UK’s extradition arrangements with the US. However, the review conducted by the Home Office headed by Sir Scott Baker found that there was no real difference between the two tests. 

Joint Investigations

As a current member of the EU we are subject to the following framework agreement:

The Agreement of Mutual Legal Assistance between the European Union and the United States of America of 2010.

This provides a framework for individual bilateral treaties to operate. However, the position of electronic data changed on the 3rd October 2019. The United States Cloud Act (Clarifying Lawful Overseas Use of Data) of 2018 resulted in a UK-USA pact of October 2019 replacing all previous processes doing away with the Mutual Legal Assistance Treaties and the need for Letters of Request.

This allows US investigators to directly approach say UK investigators for electronic data without further judicial or constitutional involvement. US investigators can now go direct to tech companies in the UK and vice versa for emails, documents and other communications stored on servers and the internet. It also allows US investigators to enter into agreements and supply overseas investigators with information on suspects for example in the UK.

This, however, is merely formalising what was already happening for example City of London Police had already entered into a Memorandum of Understanding dated 20th March 2015 with US Immigration & Customs Enforcement and Homeland Security to share intelligence and assist each other in investigations and prosecutions either side of the Atlantic in relation to fraud and intellectual property crime.

Arguably, the downside of this is that it allows law enforcement agencies to bypass constitutional (US) and judicial (UK) scrutiny potentially leading to potential miscarriages of justice. It could arguably allow the US to send Human Rights sensitive data to countries where lives may be endangered. This cooperation is at odds with the 4th Amendment to the Bill of Rights circumventing the need to show ‘probable cause’ in searching for evidence.


The US disclosure regime is not unlike that operating in the UK but is different in several respects.  It would appear a reality that whilst passing of electronic evidence over the Atlantic has become easier, obtaining disclosure as defence lawyers from the US remains problematic if not impossible.

CPS Duties on International Disclosure

The CPS have discharged their duties to obtain third party material in the US if they have taken reasonable steps to obtain that material.  The UK courts determine if they have discharged that duty if they are met with a refusal to cooperate by the US (R-v-Flook [2009] EWCA Crim 682). They would have to show for example exhaustion of all methods of seeking assistance (LOR’s and reliance upon bi-lateral treaties).

US Disclosure

The essential points worthy of note are that disclosure in the US hinges on the case of Brady -v-Maryland [1963] namely suppression of exculpatory evidence by the prosecution was a violation of the Constitutional Right to due process (14th Amendment). However, because individual States and the federal government have failed to arrive at a consistent approach to so called ‘Brady rights’ of disclosure, UK defence teams seeking disclosure from the USA have little hope of cooperation. Different states have different definitions as to what constitutes exculpatory evidence (similar to the disclosure test under CPIA i.e. undermines the Crown or supports the defence) but cannot agree upon a joint definition. In short, if a US State cannot guarantee disclosure from the Federal Government (which it cannot as it invariably invokes privilege) what hope have we?

Steve Nikolich is able to advise and represent clients in any proceedings involving cross-jurisdictional investigations.

Central Chambers has a criminal team with experience in defending all manner of criminal allegations – from summary offences to the most serious indictments.

If you would like to instruct Steve Nikolich or another member of the criminal team, please do not hesitate in contacting the criminal clerks by clicking here or by calling on 0161 236 1133.