Sean Sullivan


Sean is a calm and focused barrister who both prosecutes and defends allegations of serious crime –and has acted across a wide range of cases.

Background and expertise

In more than a decade of experience, Sean has handled serious allegations such as murder, rape, historic sexual abuse, drugs conspiracies and firearms offences.

He has experience of dealing with multi-defendant cases, and those involving heavy amounts of material and complex issues of law. He is also experienced in appeal work – having appeared for clients before the Supreme Court, Court of Appeal and Divisional Court.

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He aims to manage cases proactively – giving strategic advice at an early stage. He is skilled in case preparation and both oral and written advocacy.

He is adept at winning the confidence of clients – and is known for his hard work and tenaciousness in court, even in the trickiest of cases.

Notable cases

R v J, 2018

Victim was stabbed seven times to the chest. Identified his lodger, the defendant, as his attacker. Defence involved full on attack on victim’s credibility, that his identification was wrong and that he had been attacked by someone else. Defendant acquitted of both attempted murder and wounding with intent. Birmingham Crown Court.

R v E, 2018

8 defendants aged between 14-16 accused of attempted murder and wounding with intent in two knife attacks in East London. Acting as prosecution junior during five week trial. Dealt with bad character applications and two day sentencing hearing - both complicated by the age of the defendants all of whom were convicted. Snaresbrook Crown Court.

News story here

R v H, 2018

Instructed by the National Education Union to defend, in the magistrates’ court, an allegation of assault made against a teacher by a pupil which was supported in evidence by a member of staff. Defence involved careful cross-examination of child and full on attack on staff member’s account. Defendant acquitted. Southampton Crown Court.

R v O, 2017

Defending attempted murder allegation deriving from group knife attack in night club. Ran a series of legal arguments as to admissibility of forensic and medical evidence that ensured that in due course the prosecution offered no evidence on the attempted murder and accepted a plea to ABH with the defendant receiving a non-custodial sentence. Sheffield Crown Court.

R v S, 2016

Charged with murder, Smith was the only one of five defendants to be acquitted after a five-week trial. Sean’s cross-examination of the prosecution’s cell site expert helped undermine the case. Earlier, in the divisional court, Sean had successfully challenged a decision to refuse bail.

R v FGF, 2018

Defence of university student accused of rape. His DNA was found on swab of higher vagina. He insisted that he had never penetrated complainant. Defence advanced challenged forensic evidence and suggested risk of contamination of swab due to not following correct procedure. Defendant was acquitted. Leicester Crown Court.

R v M & M, 2016

Sean, prosecuting, secured convictions against a father and son who were key players in a group of international money launderers. The case involved substantial amounts of telephone data, financial information, and covert surveillance.

Read more Notable cases

R v P and others, 2017

Sean represented three defendants accused of conspiring to supply cocaine. Sean ran legal arguments at an early stage that led to the prosecution dropping the allegation against two of the defendants; then further legal arguments at trial in relation to non-disclosure that led to the prosecution offering no evidence against the third.

Financial conduct/regulation project, 2015
Sean worked as part of a team of barristers, assisting a leading global bank with its regulatory obligations. He worked directly with bankers and executives to help them meet standards in relation to “know your client” and anti-money laundering requirements. During the project Sean worked from London, Geneva and Monte Carlo.
R v C, 2016

At the Old Bailey, Sean defended a prison inmate accused of causing ‘GBH with intent’ to a fellow inmate. After a seven-day trial involving careful and effective cross-examination of the complainant, the defendant was acquitted.

Professional Commentary and Attribution

"His easy-going manner belies the quality of his advocacy, both oral and written." (Legal 500, 2017)
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PROFILE: Sean Sullivan

‘Unafraid, and this shows in his approach to situations.’

Legal 500, 2018

Year called



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Confiscation / POCA

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Financial Crime

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Fraud, Bribery & Corruption

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Road traffic

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Sexual offences

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Regulatory / Disciplinary

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Financial and Corporate law

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VAT Tribunals


020 7489 2727


BA in jurisprudence, University of Oxford (St Edmund Hall)


CPS Panel (Grade 3) and Rape Panel

Accredited pupil supervisor

Accredited to accept direct public access instructions

Accredited to deal with vulnerable witnesses


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