Sean Sullivan is an experienced, calm and focused barrister who both prosecutes and defends allegations of serious crime. He prepares his cases with great care, gives insightful advice and is a convincing jury advocate.
Background and expertise
Sean regularly handles allegations of murder, rape, serious organised crime (including drugs and firearms) and financial crime.
Defending a man with serious mental health issues accused of murder. Led by Justin Rouse KC.
Defending the alleged hitman in an 11 week, eight defendant murder trial involving the killing of an innocent passer-by after a drive-by shooting. Led by Peter Glenser KC.
Defending, alone, an allegation of causing death by careless driving.
Defending in a five-handed murder trial. Led by Anthony Berry KC.
Prosecuting a son for the attempted murder of his disabled mother by dousing her in white spirit and setting her alight.
News report here
Defending an allegation of attempted murder. The complainant was stabbed seven times to the chest and identified his lodger, the defendant, as his attacker. Sean challenged the identification evidence and the defendant was found not guilty.
Charged with murder, S was the only one of five defendants aquitted after a five-week trial. Sean’s cross-examination of the prosecution’s cell site expert helped undermine the prosecution’s case. Earlier, in the Divisional Court, Sean had successfully challenged a decision to refuse bail. Sean was led by Justin Rouse KC.
Prosecuting a double rapist. The defendant was convicted.
Defending a man accused of multiple rapes, people trafficking and conspiracy to cause prostitution. The defendant was acquitted.
Defending a man accused of rape and attempted rape of the same complainant after supplying her with drugs. The defendant was acquitted on both counts.
Defending a young man accused of rape where a co-defendant was running a cut-throat defence. Sean persuaded the prosecution that the evidence was such that they should offer no evidence against his client resulting in a not guilty verdict.
Sean defended a university student accused of rape whose DNA was found on a swab of the higher vagina. The defendant insisted he had never penetrated the complainant. Sean challenged the forensic evidence and suggested a risk of contamination due to not following the correct procedure. The defendant as acquitted.
SERIOUS ORGANISED CRIME
Prosecuting over twenty defendants alleged to be part of an organised crime group involved in the supply of drugs, possession of firearms and an attack on the police in an attempt to retrieve seized drugs and firearms. Led by Peter Glenser KC.
H was accused of being the equal partner of the ringleader in a conspiracy to import cocaine into the United Kingdom. The drugs weighed over 1.5 tonnes and had a street value of more than £100 million. The prosecution’s case relied upon close personal and professional links to the ringleader, telephone communications and covert recordings. Sean attacked and undermined each aspect of the prosecution’s case arguing that their interpretation of the evidence was simply incorrect. The defendant was found not guilty.
Press coverage can be found here
Assisting a financial organisation engaged in global trading with financial crime compliance.
Defending a businessman accused of tying up the complainant, holding him hostage, beating him and threatening to kill him. The complainant was found bound and bloodied by the police. The defence was that he had agreed to be tied up and had set up the defendant after perpetrating a serious fraud against the defendant. Advancing the defence involved a full attack on the complainant’s character in cross-examination over three days. The defendant was acquitted on all counts.
Sean was successful in having a conviction for grievous bodily harm with intent quashed by the Court of Appeal. Sean was not involved in the original trial, but was asked to appeal on the basis of disclosure failings by the police and prosecution counsel and errors made by the trial judge. The appellant was released from serving a custodial sentence.
Professional Commentary and Attribution
"He's a fantastic barrister and a real fighter." (Chambers UK, 2024)
"An excellent advocate with a great approach to clients." (Chambers UK, 2023)
"Sean exhibits fantastic attention to detail when dealing with cases of great complexity. He is able to foster brilliant working relationships with the clients, obtaining their confidence at an early stage. He pro-actively defends cases in court, vigorously challenging disputed evidence." (Legal 500, 2023)
"He sees the wood from the trees" (Legal 500, 2020)
‘Unafraid, and this shows in his approach to situations.’ (Legal 500, 2018)
"His easy-going manner belies the quality of his advocacy, both oral and written." (Legal 500, 2017)
PROFILE: Sean Sullivan
Confiscation / POCA
Fraud, Bribery & Corruption
Regulatory / Disciplinary
Financial and Corporate law
020 7489 2727
BA Jurisprudence, St. Edmund Hall, University of Oxford.
Criminal Bar Association
CPS Panel (level 4)
CPS RASSO prosecutor
Serious Fraud Office (panel A)
Fee-paid Judge of the Mental Health Tribunal