John Warrington

Year of Call: 2000

John is a barrister specialising in professional disciplinary proceedings, regulatory and criminal law. John has particular expertise in the field of the regulation of healthcare professionals, environmental law, health and safety, serious organised crime and high-value financial crime. John is ranked as a leading criminal barrister in Chambers & Partners UK Bar Guide.

Please fill out the form below and either John or one of our highly qualified Clerks will respond within 48 hours.

The use of the Internet or this form for communication with the firm or any individual member of the firm does not establish a solicitor-client relationship. Confidential or time-sensitive information should not be sent through this form.

Alternatively, you can call us on +44 (0) 207 332 5400


John is a barrister specialising in professional disciplinary proceedings, regulatory and criminal law. Within these fields, his principal areas of interest include the regulation of healthcare professionals, environmental law, health and safety, serious organised crime and high-value financial crime. He is ranked as a leading criminal barrister at the London Bar in Chambers & Partners UK Bar Guide.

John’s criminal law pedigree lends itself well to his increasing popularity in the professional disciplinary tribunals. He often acts in sensitive cases involving tandem criminal and disciplinary issues, in particular those concerning professionals with substance misuse or mental health problems. He is also experienced in matters related to serious clinical failings. He has particular expertise in the dental and nursing professions.

Litigation relating to incidents arising from serious regulatory breaches, often involving corporate defendants, forms a significant part of John’s practice. Latterly, he has defended and prosecuted a number of toxic sewage discharge cases, as well as acting in matters of asbestos related offending.

Regularly instructed in cases of the utmost seriousness, John has acted in matters of homicide, serious violence, multi-million-pound fraud, high profile corruption and large-scale drug trafficking. His advisory work often involves instructions at the pre-charge or investigative stage. He provides advice and representation to high-profile executives and performers within the music and entertainment industries, including Grammy and Ivor Novello award-winning recording artists.

Judicial appointments

  • Fee-paid Judge of the First-tier Tribunal (Social Entitlement Chamber).

Additional Information

In addition to his busy practice, John is a qualified advocacy tutor and regularly lectures and provides training on various aspects of his core practice areas.

Professional panel appointments

  • List of Specialist Regulatory Advocates in health and safety and environmental law (List B).
  • General Dental Council (GDC) appointed advocate: Band C (10 years' call and above).
  • The Bar Standards Board (BSB) panel.
  • The London Boroughs Legal Alliance panel (Band A).
  • Crown Prosecution Service advocate panel, including the specialist Fraud, Proceeds of Crime and Serious Crime panels.

Direct Public Access:

  • John is qualified to accept instructions by way of Direct Public Access.

Professional Memberships

  • Association of Regulatory and Disciplinary Lawyers.
  • UK Environmental Law Association.
  • Fraud Lawyers Association.
  • Criminal Bar Association.
  • South Eastern Circuit.
  • North London Bar Mess.
  • Kent Bar Mess.

Crime + View All Specialist Areas

John is ranked as a leading criminal barrister at the London Bar in Chambers & Partners UK Bar Guide. His practice incorporates a broad range of offending, including homicide, serious organised crime, large-scale drug trafficking, people trafficking, firearms, serious violence and public order, dishonesty and sexual offences. Whilst historically a defence advocate, John also prosecutes and has been appointed to the Crown Prosecution Service Advocate Panel (Level 3), including the specialist Fraud, Proceeds of Crime and Serious Crime panels. He is an experienced appellate lawyer, including referrals to the Court of Appeal by the Criminal Cases Review Commission.

Cases of Note


R v H; R v P; R v Robertson; R v S; R v Dan; R v Walker; R v W; R v F [2011] EWCA Crim 2753; [2012] 2 All E.R. 340; [2012] Crim. L.R. 149; Times, December 9, 2011.

CCRC referral. Guidance as to the correct approach to sentencing in respect of historic sexual offences.

R v H; R v D; R v Chaudhury [2009] EWCA Crim. 2485; [2010] 3 Crim. L.R. 246; 1 Archbold Review, February 5, 2010.

Court of Appeal guidance re text procedures and the statutory regime for sentencing discounts for informants pursuant to the Serious Organised Crime and Police Act 2005.

R v. B & Others


R v. C & Another

Lifer attempted murder at Category A prison.

R. v. M

Death by dangerous driving.

R. v. H & Others

Largest Class A drugs seizure (£7 million) in East Midlands

R. v. B & Others

Multi-jurisdiction importation of £5 million of cocaine.

R. v. I & Others

Sophisticated cocaine and heroin “takeaway delivery” service.

R. v. G & Others

Organised national trafficking of Class A and B drugs.

R. v. G & Others

Importation of three tonnes of cannabis.

R. v. M

Triad cannabis factories yielding £1 million of product per annum.

R. v. H & Others

Joint Triad/Russian venture involving organised prostitution of trafficked females.

R. v. C & Others

Series of armed robberies.

R. v. K & Others

Sophisticated immigration deception.


General Dental Council v. E

Undertaking procedures beyond professional competence.

General Dental Council v. W

Substance misuse and offending.

General Dental Council v. C

Alcohol misuse.

General Dental Council v. G

Extensive failed diagnoses and improper treatment.

Nursing and Midwifery Council v. K

Neglect of patient.

Health and Safety Executive v. R Limited

Asbestos exposure.

Environment Agency v. T Limited

Fish kill sewage discharge.

T Limited v. B Limited

Large-scale trade effluent discharge.

T Limited v. J Limited

Toxic levels of sulphide in sewerage network.

LB Hammersmith and Fulham v. T Limited

Summonses alleging regulatory breaches stayed for abuse of process.

M v. RB Greenwich

Prohibition order on premises posing serious fire risk.

RB Greenwich v. G Limited

Gross food hygiene breaches, including rodent infestation and food contamination.

R v. W Limited

Unlawful storage of explosives.

W v. LB Islington

Validity of £90 million worth of penalty charge notices.

LB Wandsworth v. T Limited

Hallmarking breaches re high-value gold stock.

Re A

Review of premises licence.

M v. Transport for London

Restoration of hackney carriage license on appeal.

T Limited v. A

Advising as to entry to obstructed land for major flood relief scheme.

T Limited v. RB Windsor and Maidenhead

Noise abatement notice re pumping station.

T Limited v. LB Hammersmith and Fulham

Warrants of entry for largest infrastructure project ever undertaken by UK water industry.


Re P

Application for production order in high-value money laundering investigation.

R. v. C

High-value proceeds of crime proceedings related to large-scale drug trafficking.

Metropolitan Police v. M

High-value cash detention proceedings.


R. v. W

£10 million finance fraud.

R. v. M & K

Pre-charge advice to Attorney General and subsequent prosecution of corruption related to government department.

R. v. P & Others

Multi-jurisdictional money laundering of proceeds of high-value fraud.

R. v. N

High-value breach of trust fraud committed over a decade.

R. v. K & S

High-value banking fraud.

R. v. D & D

Sophisticated high-value insurance fraud and money laundering.

R. v. C

High-value charity fraud committed by leader of local council.

R. v. H & A Ltd

Laundering proceeds of £13 million carousel fraud.

R. v. A & Another

Laundering proceeds of £2 million tax credit fraud.

R. v. K & Others

Laundering proceeds of carousel fraud.

R. v. M & Others

High-value NHS fraud involving trust directors.

R. v. G & Others

Serious corruption within major financial services provider.

R. v. U & Others

Multi-million pound money laundering via Middle Eastern “hawala” banking system.