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Derek O'Sullivan KC

“A standout silk who regularly appears in high-value catastrophic injury cases. He elicits stellar market praise… ” Chambers and Partners 2024

“A true heavyweight silk. Encyclopedic knowledge of the law and procedure, yet always able to distil advice to the binary.” Legal 500 2024

Derek O'Sullivan KC is recognised as one of the country's leading Personal Injury practitioners. His practice concentrates on very high value catastrophic injury claims.

Derek was named 'Personal Injury & Clinical Negligence Junior of the Year' at the Chambers Bar Awards 2012 and then in 2013, 2014, 2015 and 2016 he was a "Star Individual" in the Chambers Personal Injury ranking for Juniors. He took Silk in 2016 and his practice has grown whilst in Silk. He is a Band 1 Leading Personal Injury Silk in both Chambers and Partners 2023 and a Leading Silk in Legal 500 2023.

Derek's practice concentrates on cases where claimants have been catastrophically injured. He has a particular expertise in relation to brain injury cases- not only cases of severe traumatic brain injury but also "subtle" brain injury cases and cases involving cumulative causes-and spinal injury cases. He is also regularly instructed in catastrophic spinal injury and amputation cases. Derek is familiar with all elements of catastrophic injury cases and is used to leading a team (including extensive medical expert evidence) defending very high value claims.

Areas of expertise

Liability and Quantum disputes

"A master tactician and strategic thinker who is always on his game. The depth and breadth of his knowledge across a wide range of issues is second to none". Chambers and Partners

Derek's practice concentrates on cases where claimants have been catastrophically injured. He has a particular expertise in relation to brain injury cases- not only cases of severe traumatic brain injury but also "subtle" brain injury cases and cases involving cumulative causes-and spinal injury cases. He is also regularly instructed in catastrophic spinal injury and amputation cases. Derek is familiar with all elements of catastrophic injury cases and is used to leading a team (including extensive medical expert evidence) defending very high value claims.

Quantum

Derek is involved with all quantum issues generally encountered by senior personal injury practitioners dealing with catastrophic injury cases. Issues which he is currently dealing with include: severe brain injury; tetraplegia and paraplegia; claimants in states of minimal consciousness; so-called subtle brain injury cases; major psychiatric decompensation consequential on severe brain injury; amputation; capacity (litigation, management of affairs and deprivation of liberty) and all issues relating to statutory funding and settlements. Derek has been involved with claims with pleaded values in excess of £50M.

Derek has drafted a considerable number of Periodical Payment Orders and has been involved in a number of cases involving PPOs for care as well as PPOs for other heads of loss. He has also been involved in (and drafted PPOs) cases where claimants have provided reverse indemnities.

Road Traffic Accidents

Derek has conducted many cases arising from road traffic accidents and has particular expertise in the interpretation, understanding and challenging of accident reconstruction evidence. Recent cases taken to trial include: Farah v Abdullahi & 5 Ors [2020] EWHC 825, QBD; a case that involved multiple tortfeasors and insurers as well issues including the cause(s) of the claimant's extensive brain injury, novus actus interveniens and divisibility of injury, as well as Barrow v Merrett [2021] EWHC 792 (QB) and [2022] EWCA Civ 1241 as well as Arkelaos v Phillips [2021] EWHC 2321 (QB): both cases where the defendant driver was absolved of any liability following a collision with a child running into the road ahead of them.

 

Occupiers Liability

Derek has acted in a very considerable number of occupier's liability claims with the cases dealt with including:

  • Liability of the occupiers of woodlands, nature reserves, holiday parks and historic monuments
  • Liability of domestic householders in relation to the 1957 Act
  • Liability of the occupiers of commercial premises (both to visitors and persons attending in the course of their employment) in relation to the 1957 Act.
  • Liability of occupiers (both domestic and commercial) in relation to claims by trespassers under the 1984 Act.

Employers' Liability

Derek has extensive experience of acting for defendants in EL claims; in particular he has extensive experience of acting in multi-defendant cases involving accidents on construction sites. A recent case taken to trial was Harris v Bartrum [2020] EWHC 900 (QB): the employer was found not liable to the employee who suffered catastrophic injury when the articulated lorry and trailer which he had been employed to drive rolled over him.

Public Liability

Rail Claims

For many years Derek has acted for rail companies in relation to claims by passengers, trespassers and claims by injured employees. He is also instructed by Network Rail. He is familiar with the issues in rail claims (including CAHA) and has a good knowledge of the relevant Master Rule books and Railway Standards. His most recent trial acting in relation to a railway accident involved Derek acting for a train operating company being sued by a passenger after an accident in which the passenger suffered a bilateral amputation after falling between a platform and a moving train: Robinson v Greater Anglian Railways [2018] EWHC 272 (QB). This was an important decision as the claimant sought (unsuccessfully) to argue that the overall safety of train despatch systems on the rail network was unacceptable. Following this Derek acted for Network Rail/GWR in relation to a claim by a passenger who fell down an escalator at the newly modified Reading Station (thereby suffering a catastrophic spinal injury): Snell v Network Rail (2018, QBD; claim discontinued prior to trial). Derek has acted for a number of rail industry parties having been involved in claims arising from derailment as well as claims by trespassers against Network Rail/TOCs and is currently acting for Readypower Group Ltd in Rodger v (1) SPL Powlerlines UK Ltd (2) Readypower Group Ltd (2021, KBD) a case involving a rail industry worker being catastrophically injured when travelling on a MEWP when travelling from a working area to a road rail access point. 

Sport Injury and Negligence

As a keen sportsman Derek has always had an interest in sports law cases and has had frequent instructions over the years, having acted in a number of cases, including: negligent tackle claims (football and rugby) assault claims (football, rugby and ice hockey) catastrophic injury arising from golfer's negligence (jogger blinded by errant golf ball) and a claim against the Football Association (in relation to its rules on banning players following red cards and accumulations of yellow cards). In a recent rugby case Derek was instructed by Cardiff Blues in respect of the High Court claim brought by Owen Williams against the Cardiff Blues and 5 other Defendants following the catastrophic spinal injury suffered by Owen Williams whilst playing in competition in Singapore in 2014.

Derek has also represented a number of sports clubs in respect of employer's liability claims; including a Premiership rugby club accused of negligence in the rehabilitation of a player after injury.

Derek is also involved in representing amateur clubs and is familiar with claims being brought by members against unincorporated associations.

Derek is currently involved (on behalf of the WRU) in the prospective claims being advanced by former professional rugby union players against the IRB, RFU and the WRU in relation to brain injury and neuro-cognitive disorder.

Harassment

Derek was part of the Counsel team acting for the former King of Spain in Zu Sayn-Wittgenstein-Sayn v His Majesty Juan Carlos Alfonso Victor Maria de Borbon y Borbon [2023] EWHC 2478. This claim involved the Claimant seeking damages in excess of $120M from the former King of Spain by reason of alleged harassment under the Protection from Harassment Act 1997 and direct infliction of personal injury. This complex claim was subject to a lengthy hearing in June 2023 and Mrs Justice Collins-Rice struck out the entire claim in her judgment handed down on 6th October 2023. 

Road Traffic Indemnity/Policy Coverage Claims/Claims involving the MIB

Derek also specialises in acting for Insurers in relation to indemnity disputes and coverage claims arising in road traffic accident claims. Such disputes often give rise to issues relating to Article 75 of the MIB’s Articles of Association and the MIB’s Uninsured Drivers Agreement and the Untraced Drivers Agreement. 

Issues in recent cases include: 

  • Use of the vehicle being outside the scope of SDP Cover enabling insurers to argue no responsibility as contractual insurer or to satisfy a judgment under s, 151 RTA 1988 (and thus have the status of Article 75 Insurer). 
  • Use of the vehicle being for criminal purposes and thus not being for SDP purposes.
  • Passenger claim falling with the s. 151(4) RTA 1988 exemption as well as Clause 8 of the Uninsured Drivers Agreement. 
  • Article 10 of the Codified Directive and the MIB’s liability (per Colley v Shuker) to satisfy a judgment obtained by a passenger (despite clause 8 of the Uninsured Drivers Agreement). 

Cross-border claims and International Injury

Aviation accidents

Derek is instructed in relation to personal injury claims arising from accidents aboard aircraft (both fixed wing and helicopters). Derek has dealt with Montreal convention cases together with non-Convention cases where liability for the accident is in dispute; Derek was instructed by aviation insurers for the aircraft owner in the case of Day v Tasker et al (2009) QBD, Leeds DR.

Derek has also acted for aviation companies and airports in relation to "airside" issues; e.g. he was previously a London airport in relation to an industrial illness claim (by an airside worker) involving alleged breaches of the Control of Substances Hazardous to Health Regulations.

Accidents at Sea

Employer's Liability Claims involving accidents at sea or on-board ships; Derek has wide experience in this niche area and has experience of cases involving the following:-

  • The Shipbuilding and Ship-Repairing Regulations 1960
  • The Docks Regulations  1988
  • The Merchant Shipping and Fishing Vessels (Health Safety & Welfare) Regulations 1997
  • Liability generally where UK regulations do not apply

Accidents abroad

For many years Derek has acted for insurers in relation to claims arising from personal injury accidents abroad and so conflicts of laws/Rome II issues are frequent in Derek's practice. He was previously Junior Counsel in a cross border case (involving catastrophic injury) where the damages claim was pleaded at over £40m and then subsequently as Leading Counsel for one of the parties in a cross border claim (resulting from an accident in France) where the damages were pleaded at an even higher figure. Derek has experience of foreign law claims involving: French, Spanish, German, Italian, Norwegian, Belgian, Serbian, Kuwaiti, Brazilian and Maltese law.

Insurance Fraud

Derek has a particular interest in fraud in personal injury cases and is instructed in cases with a (potentially) high value but where issues of fraud or fundamentally dishonest arise. The advent and consequences (in relation to QWOCS) of fundamental dishonesty under s. 57 Criminal Justice and Courts Act 2015 has changed the landscape in relation to how insurers deal with potential fraud in claims and Derek is regularly instructed in cases involving consideration of fundamental dishonesty.

Health and Safety

Accidents at work/deaths at work can result in both criminal proceedings against the employer in question as well as private law claims for damages arising from the accident. Insurers tend to be involved in both proceedings and since commencement of his practice Derek's practice has always involved representing companies or individuals being prosecuted under the Health and Safety at Work Act/daughter legislation as well then acting for them in any subsequent civil proceedings (or inquests).

Derek frequently receives instructions from the employer's liability insurers of companies and individuals who are facing health and safety prosecutions in the criminal courts and he is very experienced in relation to trials in the magistrates court (e.g. R v Bestway Coventry Magistrates Court; a case under s. 3 of the Health and Safety at Work which involved a so-called "HTML defence") and the Crown Court with a jury (e.g R v Thomas and R v County Mall Management Limited).

Cases in which Derek has been involved in his practice include prosecutions brought under:-

  • Sections 2, 3 and 7 of the Health and Safety at Work Act etc. 1974
  • The Workplace (Health Safety and Welfare) Regulations 1992
  • The Manual Handling Operations Regulations 1992
  • The Health and Safety (Display Screen Equipment) Regulations 1992
  • The Personal Protective Equipment Regulations 1992/1998
  • The Control of Substances Hazardous to Health Regulations 1988/1999/2002
  • The Construction (Health Safety & Welfare) Provisions 1996
  • The Provision and Use of Work Equipment Regulations 1992
  • The Management of Health and Safety at Work Regulations 1999
  • The Electricity at Work Regulations 1999
  • The Work at Height Regulations 2005
  • Lifting Operations and Lifting Equipment Regulations 1998
  • Construction (Design and Management) Regulations 2007/2015
  • Control of Asbestos at Work Regulations 1987/Control of Asbestos at Work Regulations 2006/2012

Gross Negligence Manslaughter and Corporate Manslaughter

Derek is one of the few Counsel who has acted in both a gross negligence manslaughter case (R v English Brothers, Northampton Crown Court) and a corporate manslaughter case (R v Cavendish Masonry, Oxford Crown Court). He was recently instructed in another such prospective case (in which the prosecuting authority chose not to proceed after a number of submissions made by the prospective defendant).

Policy Coverage

Insurance

Derek has considerable experience in disputes arising by reason of fraud/material non-disclosure/misrepresentation in insurance claims. He has represented insurers in a number of such cases which have proceeded to trial (e.g. Savash v Co-Op General Insurance) and which have dealt with the following

  • Presentation of fraudulent documents/use of fraudulent devices in support of claims.
  • Presentation of fraudulent claims
  • Material non-disclosure in claims
  • Material non-disclosure/misrepresentation in insurance proposals.

He is currently involved (for insurers) in a number of such ongoing cases.

Derek has also been instructed in disputes involving policy coverage issues. Cases in this area include insurers refusing to provide public liability cover to a footballer who recklessly injured a fellow player, insurers refusing to provide public liability cover to an insured who injured a friend whilst engaging in horseplay with an air-rifle and insurers refusing to provide cover in respect of a fire which had been wilfully/recklessly started.

Product Liability

Derek has been regularly instructed over the years by insurers in product liability claims; the cases he has been involved in range from being instructed in the "the toxic leather Sofa" Group Litigation (acting for one of the many defendants) to acting for the manufacturers or suppliers of: bicycles, plumbing equipment, air hoses, butane gas canisters, baby changing stations, televisions, truck tyres, car tyres, motorcycle tyres, bicycle tyres etc.

Group Litigation

Derek was instructed in the "the toxic leather Sofa" Group Litigation (acting for one of the many defendants) and is currently instructed as Leading Counsel in relation to the claims (including personal injury and property damage) arising from the New Ferry explosion in 2017 as well as being instructed in the prospective claims advanced by former professional rugby players.

Civil Liability Group ADR Scheme

Derek's seniority and reputation in the personal injury "marketplace" has led to numerous requests for him to act as a QC Mediator in personal injury litigation (and litigation or disputes, such as coverage and insurance disputes arising between motor insurers following a multi-vehicle accident, arising out of personal injury claims). He accepts instructions to act as a QC Mediator and uses his long experience of this litigation to assist parties (not just Mediations involving a claimant and defendants but also as between defendants) who require the involvement of a QC Mediator. He has a fair-minded and "hands on" approach which the parties in Mediation conducted by him have found to be of great assistance and is currently instructed to act as a QC Mediator in a number of cases in which the parties have been unable to achieve settlement by the conventional means of a Joint Settlement Meeting conducted by the parties (or have not believed that a JSM would be a worthwhile exercise due to the differences between the parties).

Recommendations

  • “A standout silk who regularly appears in high value catastrophic injury cases. He elicits stellar market praise for his technical ability and client care as well as his handling of fraud allegations. He is one of the few barristers to have been instructed in a corporate manslaughter case”. “A very smooth advocate who wins everybody over with persuasion”. “A master tactician and strategic thinker who is always on his game. The depth and breadth of knowledge across a wide range of issues is second to none”. Chambers and Partners 2018- 2024
  • “A true heavyweight silk. Encyclopedic knowledge of the law and procedure, yet always able to distil advice to the binary.” Legal 500 2024
  • “Tenacious, thorough and an excellent advocate.” The Legal 500 2022
  • “Phenomenally good, his pleadings are a work of art.” “He’s completely on the ball excellent with clients and an excellent all-rounder”. “Excellent relationships with the lay clients and very good at handling expert witnesses”.
    Chambers and Partners 2017
  • “Excellent and charismatic; a fighter” Legal 500 2017
  • “He never loses sight of commercial reality” Legal 500 2017