Arna Mathiesen

Arna is an Associate in the White Collar Crime & Investigations team. She advises individuals accused of a wide range of serious criminal conduct, including money-laundering, fraud, corruption, bribery, violent offences, sexual offences and export and trade control offences.

Arna also has experience acting in high-profile extradition proceedings and advising individuals giving complex and technical witness evidence in large-scale criminal investigations.

Arna is a member of the London Criminal Courts Solicitors' Association, the Young Fraud Lawyers' Association and the Defence Extradition Lawyers Forum. 

Key Experience

• Acting for a former director of a gambling company charged with complex conspiracy to defraud and conspiracy to bribe offences, in a joint HMRC and Crown Prosecution Service (CPS) investigation.
• Acting for a high-profile client subject to successive extradition requests from a Part 1 territory under the UK-EU Trade and Cooperation Agreement (TCA) and a Category 2 territory on allegations of complex, high-value fraud, bribery and money-laundering offences.
• Advising clients at police stations arrested and interviewed under caution for serious violent offences and sexual offences.
• Acting for a senior employee investigated by HMRC in relation to alleged export and trade control offences in the course of providing private maritime security services abroad.
• Acting for a high-profile businessman accused of historic sexual offences in multiple jurisdictions, resulting in significant reputational and business risk to the client and his family.
• Acting for directors of a specialist tax advisory firm investigated by HMRC on allegations of a large-scale tax fraud exceeding £100m in value.
• Acting for an individual providing witness evidence in a large-scale criminal investigation by the Metropolitan Police into a high-profile public disaster of national significance.
• Preparing written submissions to the European Court of Human Rights concerning potential serious violations of a requested person's art. 5 rights during and following his pre-trial detention and extradition from the United Kingdom to a Part 1 territory.

Career History

Associate, Mishcon de Reya LLP
Trainee Solicitor, Mishcon de Reya LLP
University College London (UCL), LLB Law
The University of Law, Legal Practice Course (LPC MSc)

Articles and Publications

"The limits of double criminality in the Supreme Court Case of El-Khouri v Government of the United States", LexisPSL News Analysis