Simon Mayo QC
Simon specializes in serious and complex crime. He is recognised as a leader in his chosen fields of practice, and his skill and expertise continue to be in high demand by both defence solicitors and prosecution agencies. He is consistently ranked as a leading silk in Chambers and Partners.
“An excellent leader who is extraordinarily diligent and very empathetic with clients.”
“Everything you could hope for in a leader.”
“An accomplished advocate who has a sound legal mind and is very pleasant with it.”
“A consummate professional.”
“An excellent handler of witnesses in chief and cross-examination” – Legal 500, 2020
“A consummate professional” – Legal 500, 2020
Simon Mayo QC has been ranked as band 2 for Crime QC for Chambers and Partners 2020
“Very smart and has good strategic sense.”
“He’s meticulous in his preparation, thoughtful and calm in his presentation and extremely personable.”
Simon Mayo QC has been ranked band 1 for Financial Crime QC for Chambers and Partners 2020
“Extraordinarily diligent and thinks through every angle of a case. He deals with cases with the utmost care.”
“In court Simon is everything you would expect from a leading fraud silk. He makes it look effortless. He is always on top of his brief and he quickly secures the confidence of the tribunal.”
Practice Areas
Simon Mayo is recognised as a leading specialist in the field of complex fraud and business crime. He has a wealth of experience in handling cases involving serious fraud and business crime, including those centred on the financial markets, revenue frauds, and allegations of corruption both in the UK and internationally. His experience and expertise in these areas is regularly called upon by leading law firms and specialist prosecution agencies.
He has been on the SFO’s specialist QC panel for many years and is one of a small group of leading silks who has had direct experience of dealing with a deferred prosecution agreement (DPA) from initial engagement through to successful conclusion. He also acts for the Financial Conduct Authority in relation to the investigation and prosecution of malpractice and fraud in the financial services sector.
He is able to provide prompt and clear advice to individuals and corporate bodies on a wide range of issues relating to director and corporate liability for criminal and regulatory offences.
He also has expertise in data protection law and has provided legal and strategic advice to individuals and corporate clients facing investigation arising out of data breaches. In addition, he was consulted by the ICO in relation to the largest investigation into alleged data breaches that it has undertaken to date.
In the field of general crime, he has extensive experience in dealing with the homicide and other offences of the utmost gravity, including those involving complex expert evidence.
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Criminal Defence
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Simon has a wealth of experience in homicide cases and is regularly instructed as leading counsel in such cases on behalf of the defence.
He has also gained considerable experience in dealing with cases involving explosives and firearms.
The following is an illustrative list of cases in which Simon has been instructed:
R v D – Murder of a child who was alleged to have been groomed through an Internet gaming sit.
R v S – Alleged plan to detonate a bomb on a Pakistan Airlines Boeing 777 bound for the UK
R v R – Murder arising from a drug turf war
R v J – Gangland execution and decapitation
R v K – Attempted murder by nurse administering drug overdose to hospital patient
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Criminal Prosecution
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Simon has a wealth of experience in homicide cases and is regularly instructed as leading counsel in such cases on behalf of the prosecution.
He has also gained considerable experience in dealing with cases involving explosives and firearms.
The following is an illustrative list of cases in which he has been instructed:
R v B – Alleged murder of 8-week old child – so called “shaken baby” case involving expert evidence from six separate areas of medical specialisation
R v P – Eminent consultant surgeon who performed unnecessary major surgery on his patients
R v S – Attempted murder of members of a police surveillance team
R v S – Attempted murder of three women as they slept in their beds at central London hotel
R v M – Husband who secretly administered abortifacient drugs to his wife
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Fraud & Financial Crime
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Simon Mayo is recognised as a leading specialist in the field of complex fraud and business crime. He has a wealth of experience in handling cases involving serious fraud and business crime, including those centred on the financial markets, revenue frauds, and allegations of corruption both in the UK and internationally. His experience and expertise in these areas is regularly called upon by leading law firms and specialist prosecution agencies.
He has been on the SFO’s specialist QC panel for many years and is one of a small group of leading silks who has had direct experience of dealing with a deferred prosecution agreement (DPA) from initial engagement through to successful conclusion. He also acts for the Financial Conduct Authority in relation to the investigation and prosecution of malpractice and fraud in the financial services sector.
The following is an illustrative list of cases in which he has been instructed:
R v R, G and Ors – The largest tax fraud ever prosecuted by HMRC
R v N and Ors – International investment fraud prosecuted by the FCA
R v G – SFO investigation into international bribery and corruption
R v R, D and Ors – Advance fee fraud prosecuted by the SFO
R v HK – Wine Investment fraud targeting American professionals
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Regulatory Law
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Simon advises individuals and corporate bodies on a wide range of regulatory issues.
He is able to advise on all issues affecting director and corporate criminal liability including that under the Corporate Manslaughter and Corporate Homicide Act 2007
He has advised in relation to the ICO investigation into suspected data protection breaches by Cambridge Analytica and Facebook
He has also been instructed to advise in respect of criminal and quasi-criminal aspects of data protection law in the Channel Islands (Jersey)
Professional Memberships
- Criminal Bar Association (Former member of the Executive Committee)
Awards, Qualifications & Other
- Queen’s Counsel (2008)
Direct Access
Simon Mayo QC is approved to accept instructions direct from international and UK clients on a direct access basis, without the need for a solicitor to be instructed in appropriate cases.
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