Siza Agha has been instructed as leading junior counsel in an array of long multi-handed trials for over 10 years and therefore brings with him a vast amount of experience dealing with the most complex cases.

Siza is instructed on several cases involving “Encrochat” arising out of Operation Venetic and is considering the legality of the intercepted material in the UK, France and the Netherlands as well as the integrity, reliability and general admissibility of the product that the NCA are currently serving as evidence. Siza has previously been instructed and successfully challenged the use of similar material in cases involving interception of conversation from prison, admissibility of probe material authorised in the UK but generated in Europe and the taping of legally privileged conversations at police stations.

Siza has been involved in extensive advisory work that includes a group of ex-premiership players who had been victims of an extensive “Ponzi fraud” and an English businessman in Dubai on talking a private prosecution against his wife and daughter.

Siza has advised extensively on sporting matters in particular football and athletics. He has represented/advised players/mangers/clubs across the whole football pyramid, high profile international athletes and a number of other sports people. He has advised and appeared in disciplinary, selection and dispute resolution matters in a number of sports from MMA to Ice skating and has been quoted extensively in the media on many sporting matters. He has been registered as an agent/intermediary at the Football Association and an IAAF Athlete Representative for many years. Siza was featured as ‘lawyer of the week’ in The Times for his work in sport.

Legal Expertise

Financial Crime overview

Siza is regularly instructed in multi-handed matters concerning financial crime. He is regularly instructed as Leading Counsel in complex cases.

Notable Financial Crime cases

Operation Mamba

£13 million mobile telephone fraud.

Operation Belgium

Money laundering - case stayed collateral challenge.

R v Radford

Supply and manufacture of counterfeit coins.

Crime overview

Siza has built a long and established practice defending those charged with offences such as murder, attempted murder, money laundering and drugs offences.

Notable Crime cases

R v Gripshi

International money laundering and drugs involving one of largest seizures.

R v Mohammad

Conspiracy to murder.

R v White & Others

International drugs and money laundering.

R v Okpala

Murder case involving anonymity of witnesses.

Current & Recent Cases

Operation Cranfleld
Multi-handed conspiracy to import and supply of cocaine brought in speciality adapted hides in a Robinson Helicopter at Southwark Crown Court.

Operation Globemaster
Multi-handed conspiracy to manufacture and supply of counterfeit passports at Inner London Crown Court.

Operation Chapman
Multi-handed conspiracy to supply machine guns at Harrow Crown Court.

Operation Varangi
Multi-handed at Blackfriars Crown. High profile case involving extensive importation of Class A drugs in the roof of a Bentley.

R v M
Represented the principal defendant in a multi handed international people trafficking case involving extensive surveillance and audio probe material.

Operation Zurna
Multi-handed conspiracy to manufacture and supply credit cards at Inner London Crown Court.

Operation Pearlwart
Conspiracy to supply class A drugs. Case involved extensive surveillance operation with defendant having 52 mobile phones over a period of 18 months at Snaresbrook Crown Court.

Operation Tallassee/Wheeler
Multi-handed conspiracy to supply class A drugs and money laundering at the Central Criminal Court.

Operation Kernow
Multi-handed drugs conspiracy at the Kingston Crown Court.

Operation Mudde
Multi-handed conspiracy to supply class A drugs at Kingston Crown Court.

R v K
Multi-handed conspiracy to rob at the Central Criminal Court – planned robberies involving firearms.

B Oil
Multi-handed Trading Standards prosecution at Blackfriars Crown Court.

R v K
Multi-handed Diversion fraud and money laundering at the Leicester Crown Court.

E Group
Multi-handed Trading Standards Prosecution at Birmingham Crown Court.

R v P
Multi-handed international cannabis importation.

Reported Cases

R v Mary Druhan
Miscarriage of Justice Case. Reference to the Court of Appeal by the CCRC.

R v Randel [2004] 1 All ER 467
The test for bad character material being adduced by a co-defendant in a cut-throat defences.

R v Hayes [2002] All ER (D) 06 (Aug)
Reference from CCRC on the scope of intention in murder and recklessness.


Operation Mamba
£13 million mobile telephone fraud

Operation Belgium
Money laundering – case stayed collateral challenge

R v Radford
Supply and manufacture of counterfeit coins

R v Ayyildiz
Money laundering £200 million

Operation Stamford
Credit card fraud

Operation Birhakeim
Conspiracy to defraud

Operation Trinity
Mortgage fraud and money laundering

Operation Effare
National Crime Squad fraud case

Operation Figural
Conspiracy to manufacture and supply counterfeit passport to undercover officers.

Operation Nail
Conspiracy to defraud banks

Operation Minneola
Manufacture and supply of counterfeit passports – largest seizure in the UK


R v Gripshi
International money laundering and drugs involving one of largest seizures.

R v Mohammad
Conspiracy to murder

R v White & Others
International drugs and money laundering.

R v Okpala [Central Criminal Court]
Murder case involving anonymity of witnesses

R v Fitzgerald [Central Criminal Court]
Multi-handed murder case

Operation Pauldings
Case involving “supergrass” (section 73 SOCPA procedure) admissibility re “coaching of witnesses”)

R v D
A case involving informants

R v Goren
International money laundering and drugs

R v West
Large scale importation of Class B drugs in halon gas canisters

R v Aksu
Importation of £60 million of heroin)

R v Turgut
Conspiracy to import heroin and money laundering – trial lasted nine months

R v Hamilton
Manufacture and supply of firearms

The Appeal of Mary Druhan
Murder conviction referred back by the CCRC

The Appeal of Terence Brett
Conviction referred back from 1963

R v Haghikiriaku
Undercover operation involving steroids

R v Flourentzous
VAT evasion on cigarettes

R v Potter
Perverting the course of justice

R v Aderdour
Quadruple murder

R v Adan
Importation of 200kg heroin

Operation Pancrack
Distribution and supply of heroin – admissibility of prison tape material)

Operation Dottery
Distribution and supply of heroin

R v Downes & Others
Supplying 2 tonnes of cannabis – abuse of process – case stayed manipulation of the disclosure)

R v Sutherland & Others
Conspiracy to murder – case stayed breach of legal privilege)

R v Sentence v Others
Conspiracy to supply heroin – case stayed breach of legal privilege)

Operation Casino
Customs & Excise – Class A and B drugs

Appeal of Dennis Hayes
CCRC appeal – murder from 1984 – development on the law of intention

R v Randall [House of Lords Appeal]
Murder case – extent to which co-defendants can be cross-examined as to character

Operation Bright
200kg Class A drugs

Operation Galaxy
Conspiracy to supply Class A and B drugs and Operation Min. Conspiracy to murder. Both of these cases involve taping of solicitors/client conferences and abuse of process

Operation Casino
Conspiracy to supply class A and B drugs

Operation Abetted
Supplying 200 kg of heroin

R v Long & Others
Importation of 400 kg of heroin

Operation Cloverbank
Conspiracy to supply Class A and B drugs

Operation Ocre
Leading junior counsel in a human trafficking case

Operation IBSOSS
Operation Trident case – shooting in a nightclub)

Operation Sleave
Leading junior in a drugs case

Operation Themis
15 handed – selling drugs to undercover officers

R v Yilmaz
Drugs – PII – special counsel and abuse of process

R v Jacobs
Operation Trident case – supplying ammunition and firearms to undercover officers

  • British Association of Sports & Law
  • Post graduate certificate in sports law
  • LLB
  • Accredited PDSL mediator, January 2021

I, Siza Agha, am a data controller and can be contacted at 3 Raymond Buildings, Gray’s Inn, London WC1R 5BH or by telephone on 020 7400 6400 or by email at My Data Protection Policy can be found below.

All personal data that I process is for the purposes of providing legal services, conducting conflict-checks, marketing, defending potential complaints, legal proceedings or fee disputes, keeping anti-money laundering records, training other barristers and pupils and when providing work-shadowing opportunities, and/or exercising a right to a lien. The types of data I process vary upon the nature of the legal matter in relation to which I am engaged to advise, but can include names, contact details, biographic details and ‘special category personal data’ (such as details of racial or ethnic origin, political opinions, religious or philosophical beliefs, health, sex life and criminal convictions and proceedings).

Depending upon the circumstances of the case, the legal bases upon which I process personal data are (i) the performance of a contract to which the data subject is a party or in order to take steps at the request of the data subject prior to entering into a contract, (ii) the processing is necessary to comply with legal obligations to which I am subject, or (iii) the processing is necessary for the legitimate interests set out above, except where such interests are overridden by the interests or fundamental rights and freedoms of the data subjects which require protection of personal data, in particular where the data subject is a child. When I rely on (iii) legitimate interests, my ‘Legitimate Interests Assessment’ can be found here. When I process data which has not be obtained directly from the data subject (e.g. personal data contained in evidential materials), it will have been supplied to me as part of my instructions in circumstances covered by legal professional privilege.

Depending upon the circumstances of the case, I may share the personal data with:

  1. my Chambers, which supplies professional and administrative support to my practice;
  2. Courts and other tribunals to whom documents are presented;
  3. my lay and professional clients;
  4. potential witnesses, in particular experts, and friends or family of the data subject;
  5. solicitors, barristers, pupils, mini pupils and other legal representatives;
  6. ombudsmen and regulatory authorities;
  7. current, past or prospective employers;
  8. education and examining bodies;
  9. business associates, professional advisers and trade bodies.

I retain personal data for no longer than 7 years after the case has come to an end or as otherwise required by law.

I do not intend to transfer data to any country which is not either within the European Union, ‘white listed’ by the EU or otherwise permitted by EU law (e.g. to the USA under the provisions of the ‘Privacy Shield’).

Under the GDPR, data subjects whose personal data I process have the right to request from me access to, and rectification or erasure of, their personal data, the right to the restriction of processing concerning them, the right to object to processing as well as the right to data portability. Data subjects also have the right to lodge a complaint with the Information Commissioner’s Office (

In cases where there is a contract between me and the data subject, the provision of personal data is a contractual requirement and the data subject is obliged to provide the personal data in order that I can supply legal services. A failure to provide such data may mean that I will not be able to provide the legal services.

Rev 1.1 – 12.06.2018

Data Protection Policy

Legitimate Interests Assessment

Siza Agha is qualified to accept instructions direct from clients under the Bar Council’s Public Access Scheme. This means that members of the public who seek specialist advice can come direct to him. In addition, he welcomes instructions from solicitors, in-house law departments, qualified foreign lawyers, and clients licensed by the Bar Council to give instructions direct to barristers under the Bar Council’s Licensed Access Scheme.

For further information please contact our Clerks.