”Individuals in Cross-Border Investigations or Proceedings: The UK Perspective” chapter for The Practitioner’s Guide to Global Investigations

”Individuals in Cross-Border Investigations or Proceedings: The UK Perspective” chapter for The Practitioner’s Guide to Global Investigations

BCL’s Richard Sallybanks and Greta Barkle have co-authored the chapter ‘Individuals in Cross-Border Investigations or Proceedings’ in the seventh edition of Global Investigations Review: Practitioner’s Guide to Global Investigations.

*Here is a short extract from the guide. If you wish to read the full guide please visit Global Investigations Review website.

40.1 Introduction

In any cross-border investigation, invariably suspects will be located in different jurisdictions or subject to investigations by authorities from different jurisdictions, or both.

This chapter looks at the key issues that can arise when acting for an individual present in the United Kingdom who is subject to criminal investigation or proceedings in one or more overseas jurisdictions, or who is facing parallel proceedings here and abroad.[2]

40.2 Cross-border co-operation

The United Kingdom might co-operate with overseas agencies or regulators in various ways when investigating or prosecuting an individual, ranging from informal ‘intelligence sharing’ to mutual legal assistance (MLA). The main domestic legislation governing MLA in the United Kingdom is the Crime (International Co-operation) Act 2003 (CICA), Part 1 of which deals with criminal cases.

The United Kingdom is party to a number of bilateral and multilateral MLA treaties. While it is not necessary for an MLA treaty to exist between the relevant countries for a request to be made under CICA, requests are more likely to be successful where a treaty basis exists. Co-operation with EU Member States was changed by the United Kingdom’s exiting of the European Union. On 24 December 2020, the United Kingdom and the European Union signed the UK-EU Trade and Co-operation Agreement (TCA), which includes specific provisions on co-operation and MLA, and facilitates the application between EU Member States and the United Kingdom of certain previous MLA treaties and conventions.[3] While the TCA ensures there remains a strong co-operative relationship, certain investigative tools, such as European investigation orders,[4] can no longer be used.[5]

MLA requests are usually made to the UK Central Authority (UKCA)[6] through a formal international letter of request. In March 2022 the UK Home Office updated its detailed guidance on how foreign authorities can make such requests.[7] MLA requests will only be considered appropriate when the request is for evidence (and not intelligence).[8]

A formal MLA request is not required where overseas police and other law enforcement agencies request assistance directly from their UK counterparts. A number of UK agencies[9] can receive direct requests, and often this form of co-operation (also known as mutual administrative assistance) is governed by data sharing agreements or memoranda of understanding.

In some instances, cross-border co-operation may extend to the establishment of a joint investigation team (JIT) between investigating agencies in more than one country.[10] Creating a JIT is another way information or evidence can be shared without the need for MLA.

*The guide was first published by Global Investigation Review on 4 January 2023. If you wish to read the full guide please visit Global Investigation Review website.


A partner in BCL for 20 years, Richard Sallybanks has been involved in numerous UK and international business crime investigations and prosecutions. His core practice is defending senior executives who are suspects in investigations. His SFO experience includes the Airbus, Barclays Qatar, Alstom and Kaupthing Bank investigations as well as successfully defending Tesco’s Commercial Director on charges of an alleged £250m accounting fraud. Many of his cases are cross-border and Richard is experienced in managing and co-ordinating teams of lawyers in multi-jurisdictional investigations. In the financial sector he has acted for bankers, brokers, traders and senior executives in criminal and regulatory investigations, by the FCA and overseas authorities, including in relation to allegations of money laundering, insider dealing and market abuse.

Anoushka Warlow is a partner specialising in acting for individuals in complex, multi-jurisdictional, allegations of serious fraud, bribery and corruption.  She has been involved in many high-profile investigations and prosecutions brought by all the major domestic and international enforcement agencies.

Greta Barkle is a New Zealand qualified lawyer specialising in business crime, regulatory investigations, extradition and cybercrime. Prior to joining BCL Solicitors LLP, Greta worked on a range of complex disputes, including claims against the New Zealand Police and Government Communications Security Bureau in relation to dawn raids and unlawful surveillance of communications. Greta also assisted counsel in New Zealand’s leading white collar crime and extradition case and is an experienced criminal and regulatory prosecutor.

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