Robert O'Sullivan KC

R v Harrison (Hereford CC)

Prosecuting the Treasurer of West Mercia Police Federation for fraud by abuse of position for 8 years of misappropriation of his members’ funds and dishonestly claiming salary payments when off work.

R v Cazaly and others (St Albans CC)

Prosecuting for Hertfordshire CC six defendants for fraudulent trading arising out of a non-regulated wine investment scheme with 41 mostly vulnerable and elderly clients.

R v ZK and others (Birmingham CC)

Prosecuting 14 defendants over a series of trials arising from the cheating of English language tests at a private education college.

R v AB, CD (Southwark CC)

Prosecuting for the SFO two Deferred Prosecution Agreements arising from corruption in the commercial office fit-out sector. Involved appeal by way of judicial review to the Divisional Court [2026] EWHC 337 (Admin), relating to naming in DFA Judgment of defendant acquitted at associated trial.

R v Scully-Hicks (Cardiff CC)

Defending a father accused of the murder of his infant daughter, involving advising and cross-examining on all aspects of ‘shaken baby syndrome’ including neuropathology, vitamin D deficiency and Ehlers-Danlos syndrome.

R v Hayley and others (Birmingham CC)

Prosecuting at trial, and successfully in the Court of Appeal against a half-time terminating ruling, a £98 million marketed tax avoidance scheme which exploited the income tax relief available in respect of losses incurred in the development and pre-production of UK based feature film projects. Also representing CPS POCU in the long-running confiscation proceedings under the CJA 1988.

R v Urumov and others (Southwark CC)

Prosecuting a team of fixed income traders at the City branch of a Russian bank who conspired to defraud their employers of circa USD160 million by the false pricing of Argentinean peso sovereign warrants.

R v Moseley (Preston CC)

Prosecuting a murder where a father sought to blame his 14 year-old son for discharging a shotgun into the chest of the victim on the doorstep of their home.

R v Day (Northampton CC)

Defending at trial and in the Court of Appeal, the indecent assault and kidnap with intent to commit a sexual offence of a 13 year-old girl.

R v Dowling and others (Croydon CC)

R v Koslowski and others (Wood Green CC)

Prosecuting two separate investigations into deaf applicants for disability assistance grant payments for defrauding the DWP of £100,000s.

R v M and others (Southwark CC)

Prosecuting 13 defendants (two trials) for a multi-million pound VAT and excuse duty fraud

R v Donnelly and others (Kingston CC)

Prosecuting 13 defendants (two trials) in a multi-million pound MTIC carousel fraud and advising on jurisdictional issues on associated money laundering operation based in Scotland.

R v Bartlett-Twivey and others (Southwark CC)

Prosecuting (three trials) conspiracy to defraud mobile network operators by the operation of GSM Gateways which used fraudulently acquired PAYG SIM airtime credit and associated statutory offence of using a COMUG Gateway without a licence contrary to the Wireless Telegraphy Act 2006.

R v Inglis (CCC)

Prosecuting, at trial and in the Court of Appeal, a mother for the so-called mercy killing of her son by lethal injection following his catastrophic incapacity as a result of a motor accident.

Robert O'Sullivan KC is a member of the Serious Fraud Office Panel of King’s Counsel. As junior counsel he was on the Attorney-General’s A List of specialist advocates and a Grade 4 CPS prosecutor.

He is a member of the Bar Council’s Law Reform Committee, with a particular interest in IPA and RIPA and the associated Codes of Practice and the tension between state surveillance and legal professional privilege and confidential journalistic sources. He is involved in the Bar’s responses to consultations on, amongst other areas, strict liability tax reporting offences, official secrets and the new Sentencing Code.

He was elected Head of Chambers at 5 Paper Buildings in November 2024.