Karl Masi

Year of Call: 2011

Karl is a barrister practising in the fields of crime and associated civil and regulatory law.

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Karl is a barrister developing a practice with a particular focus on financial crime and associated civil and regulatory proceedings.

He receives a range of business crime and fraud instructions, including cases related to the proceeds of crime and the export of controlled goods, money laundering and insider dealing. He was instructed as junior counsel to one of the Barclays’ derivatives traders charged with conspiracy to manipulate LIBOR and has been working within the Global Anti-Financial Crime department of Deutsche Bank.

Karl maintains a strong general crime practice defending and prosecuting in the Crown Court.  He has been led by senior counsel and as junior alone in a wide range of matters from attempted murder, s.18 GBH, robbery and drugs offences to theft, burglary and public order offences. 

Karl is instructed in Part 5 (Civil Recovery) and Part 6 (Tax) POCA proceedings. He appears before the High Court and the First-tier Tribunal (Tax) in a range of related matters, from applications for freezing injunctions to substantive hearings.

Building on his work in off-shore jurisdictions prior to being called to the Bar, Karl has developed experience in areas where crime and civil law cross-over. He recently spent two months based with an off-shore law firm instructed to advise on allegations of trustee fraud in several breach of trust cases within the jurisdiction.  He was also led by Gary Pons in the High Court acting for the successful applicant enforcing a multi-million pound US judgment in the UK.

Karl’s instructions in the regulatory field include financial and health care disciplinary proceedings. He was instructed by the FCA to assist with its investigation into alleged trader misconduct in the Foreign Exchange (FX) market. He has been instructed by regulators such as the GDC and appears for local authorities in a full range of matters.

Karl has experience in private prosecutions and has successfully prosecuted a multi-handed trademark infringement conspiracy on behalf of a number of high-value designer label groups.

Karl also provides both advisory and representation in a range of chancery and commercial matters from insolvency proceedings and contractual disputes to landlord and tenant litigation. 

Professional panel appointments

  • Appointed to the Attorney General's C Panel of counsel (civil) (February 2017).    
  • Appointed to CPS Advocate Panel Level 2 (2016).
  • Appointed to the General Dental Council (GDC) advocates panel (2016).

Additional information


  • Anne Goddard Scholarship, Gray’s Inn (2010).
  • William Shaw Scholarship, Gray’s Inn (2013).
  • James Hunt Advocacy Competition runner-up, Gray’s Inn (April 2013).

Prior to joining Chambers, Karl held various legal roles both in the UK and abroad. This included an off-shore firm of attorneys in the Turks and Caicos Islands where he was part of a defence team representing politicians and an international developer on corruption and fraud charges. He was also heavily involved in commercial, regulatory and employment litigation in the jurisdiction.

Karl also worked as a paralegal in the Business Crime department of Hickman & Rose solicitors where he was involved in matters relating to LIBOR, the Bribery Act 2010, multi-jurisdictional investigations and Operation Weeting (phone hacking scandal).

Karl’s other roles include working for a legal organisation in the West Bank and acting as a caseworker on death penalty appeals before the Judicial Committee of the Privy Council, the Inter-American Court of Human Rights and the United Nations Human Rights Committee.

Professional Memberships

  • Young Fraud Lawyer’s Association.
  • Association of Disciplinary and Regulatory Lawyers.
  • Criminal Bar Association.
  • Extradition Lawyers Association.

Asset Recovery, Civil Fraud & Confiscation

Karl receives instructions in asset recovery, proceeds of crime work and confiscation matters.

Business Crime

Karl is a barrister with experience in a broad range of fraud, financial and business crime matters, including proceeds of crime and the export of controlled goods, money laundering, insider dealing and FOREX. He is currently instructed as junior counsel for a Barclays’ defendant charged with conspiracyy to manipulate  LIBOR.

In addition, Karl was instructed for a six-month period by the Financial Conduct Authority to assist with its investigation into alleged trader misconduct in the Foreign Exchange (FX) market. As a consequence, Karl has obtained a detailed knowledge and understanding of the regulatory and criminal law issues that arise in such cases, as well as the manner in which such investigations are conducted by regulatory bodies, both in the UK and abroad.

Karl was instructed by Vincent Tzenguiz as part of the legal team pursuing a multi-billion-pound claim against an international chartered accountancy firm.

He was also led by Gary Pons in a multi-million pound High Court claim concerning the enforcement of a foreign judgment in the UK.

Karl is quickly developing a successful practice in Proceeds of Crime Act 2002 (POCA) proceedings and is currently instructed in a multi-million-pound confiscation hearing brought by a national regulatory authority, in which he successfully argued against the lifting of the corporate veil. He also receives instructions from the Home Office in relation to asset recovery and forfeiture proceedings. 


Karl is barrister developing a strong practice defending and prosecuting in the Crown Court. Karl has been instructed in a range of matters including robbery, theft, burglary, public order offences, drugs and offences against the person. He was led by Serena Gates representing a member of the armed forces charged with attempted murder.

Karl is currently instructed in a 10-handed fraud, representing the first defendant on charges of conspiracy to defraud and conspiracy to pervert the course of justice.

Karl is often instructed on a privately-funded basis in a range of driving matters, comprising dangerous and careless driving, drink driving offences, failing to stop after an accident and driving without a license or when disqualified.

Extradition & International

Karl is a member of Chambers’ extradition team and is regularly instructed to represent Requested Persons in first instance hearings at Westminster Magistrates’ Court, and also in appeals to the Administrative Court.

He was instructed in an appeal in the Administrative Court relating to assurances provided by the Romanian government post -Florea.

Karl was led by Ben Keith in a complex case involving a former Russian banker whose extradition was sought on charges of hijacking and endangering the safety of an aircraft. The European Arrest Warrant (EAW) followed a previous Russian request for the same incident and was the first to involve the Hague Convention.

He was instructed as second junior for the former Chairman of JSC BTA Bank Kazakhstan contesting an extradition request from the Government of Ukraine.

Planning, Property, Landlord & Tenant

Since joining Chambers in October 2013 Karl has regularly appeared in the County Court in a variety of matters including insolvency proceedings, contractual disputes and landlord and tenant litigation and has appeared in High Court injunction proceedings.

Cases of Note

SCS v Parrish [2015] EWHC 3688 (QB)

Instructed as junior to Gary Pons. Successfully enforced a multi-million pound US judgment for fraud in the High Court.

R v BP & Others

Instructed as sole counsel in a 10-handed fraud, representing the first defendant on charges of conspiracy to defraud and conspiracy to pervert the course of justice.

R v P [2015] Cardiff Crown Court

Sole counsel representing the Director of a multi-million pound waste management company in confiscation proceedings. Successfully applied against the lifting of the corporate veil. This ruling is being challenged before the Court of Appeal.

R v S [2015] Blackfriars Crown Court

Successful half-time argument of no case to answer on charges of money laundering and perverting the course of justice. Successful recovery of monies seized under cash forfeiture legislation.

R v B [2015] Southend Crown Court

Acquittal of a 19 year old female charged with benefit fraud.

R v T & R [2014] Woolwich Crown Court

Successful prosecution of a two handed burglary and possession of offensive weapon

The Government of the Czech Republic v Dogaev [2014]

Led by Ben Keith in a complex case involving a former Russian banker whose extradition was sought for endangering the safety of an aircraft. The EAW followed a previous Russian request for the same incident. Appeal pending.

The Government of Poland v Szcesniak [2014]

The Requested Person’s extradition was sought to serve the remainder of three custodial sentences in Poland. EAW discharged on Article 8 grounds.

Jasek v The Government of Poland [2013] EWHC 4186 (Administrative Court)

Appeared for the appellant challenging the rule that the Court had no power to extend time, in the case of a non-British national, for the time within which a notice of appeal had to be served on the CPS.