Oliver Cook


Specialist in defending allegations of national and international organised crime and fraud. Particularly sought after in cases which feature complex telecoms and forensic evidence including encrypted communications and low level DNA.

  • Organised Crime
  • Fraud
  • Confiscation and Asset Forfeiture


Criminal Defence

Highly sought after by those accused of the most serious criminality and frequently instructed to defend in cases with an international element, Oliver has a particular expertise in cases of trafficking drugs, firearms and explosives.

Recognised as a specialist in cases involving expert evidence he is currently defending in Operations Embossed, Estevan, Glassy, Bregwin, Rockrose and Oberon; prosecutions arising from the compromise of the EncroChat encrypted telephone network by the French and Dutch authorities.

Often instructed on a private basis in the early stages of a criminal investigation Oliver is currently advising foreign nationals facing extradition to the UK on  allegations of drug trafficking on an industrial scale.


R v L – Operation Samurai: Defendant said to be a senior member of an organised crime group with international links supplying class A drugs throughout the North West. Recovered from the crime group were multiple firearms including automatic pistols with silencers and an AK-47 assault rifle. 10 week trial.

R v O – Operation Manhattan: Defendant said to occupy a central role in a conspiracy to import millions of pounds of cocaine into the UK and distribute it nationally. Involved evidence of a ‘supergrass’. 8 week trial.

R v B – Operation Ledger: Investigation into the supply of cocaine in Kent said to be orchestrated by B from prison. 6 week trial.

R v T – Operation Broadus: Defendant said to be part of a conspiracy to supply heroin throughout the UK organised from Liverpool. 13 week trial.

R v M – Operations Prion & Karvella: Defendant said to be part of a conspiracy to supply drugs throughout the U.K including Scotland. Challenge to the timing of the Attorney General’s consent to prosecute (required in cross border cases) led to the leading Court of Appeal authority on the issue and the case being stayed. Also resulted in application for a writ of Habeas Corpus before the High Court.

R v C – Operation Sequel: Defendant said to be head of a conspiracy to supply drugs from Liverpool into Cumbria. Crown’s case relied on cell site evidence. A successful application to exclude the telephone material led to an interlocutory appeal by the Crown to the Court of Appeal. The decision of the trial judge was upheld. Acted as leading junior.


Firearms & Ammunition: 

R v R – Operation Bombay: Defendant said to be part of a conspiracy to supply drugs and firearms throughout the U.K. following the discovery of firearms, ammunition and explosives [including a viable IED] on Merseyside. 10 week trial.

R v V – Operation Blush: Defendant said to be part of a conspiracy to supply and possess firearms with intent to endanger life including an UZI machine gun and what was said to be the most criminally used firearm in the U.K. 14 week trial.



R v S – Operation Benson: Defendant said to be the head of a conspiracy to cause explosions and steal money from cash machines. 14 week trial. Acted as leading junior.

R v W – Operation Sydney: Defendant said to be part of a conspiracy to cause explosions and steal money from cash machines across the U.K. Multi agency investigation resulting in 10 week trial. Acted as leading junior.

R v P: Dispute between crime groups led to a campaign of nail bombings. The Crown alleged the defendants had contracted members of Northern Irish terror group to co-ordinate the attacks. Acted as leading junior.


Challenge to Expert Evidence: 

R v O:  Defendant linked to cache of firearms through ‘low copy’ DNA. Crown relied on ‘statistical interpretation’ of the results using software to create a ‘Likelihood Ratio. Extensive cross examination of expert witnesses including the author of the interpretation software and professor of statistical genetics at UCL.

R v P: Allegation of money laundering drugs money through businesses. Three-day legal argument and cross examination of scientific witnesses [including via link from the University of Lausanne] led to the exclusion of ‘mass spec’ evidence of drug contaminated money.

R v N & R v L:  Series of three trials in Winchester, Leeds and Worcester where the defendants were alleged to be part of a gang hijacking lorries throughout the U.K, kidnapping the drivers and stealing the contents. The Crown’s case relied on complex telephone and tracker data. Each case stopped at the close of the Crown’s case following cross examination of the prosecution telephone expert. Acted as leading junior.

Oliver defends those accused of high value and complex criminal fraud including ‘carousel fraud’, income tax, boiler room and immigration fraud.

Experienced in cases of fraud where the concealment, disposal or laundering of the proceeds of other criminality through property, businesses or international banking is alleged.

In addition to directors and company officers Oliver has experience in representing accountants and other professionals accused of concealing the proceeds of fraud and is often engaged in the early stages of a criminal investigation prior to charge.

R v A – Operation Cobweb: Accountant accused of knowingly assisting in the concealment of millions in crime group money through Ltd companies and property transactions. Negotiation resulted in the Crown accepting pleas to regulatory offences.

R v S – Education/Immigration fraud: conspiracy to breach immigration law by arranging for hundreds of proxy candidates to take Home Office approved TOIC exams. Acquitted.

R v S: Allegation of income tax fraud whereby HMRC employee diverted funds from high worth company tax accounts to pay tax liabilities of other companies for a fee. Represented officer of company whose liability was paid in this way. Acquitted.

R v R – Operation Vaulter: 6 month, 20 million-pound MTIC fraud. Linked to FCIB (First Curaçao International Bank) used to channel and conceal billions of pounds of transactions linked to tax fraud.

R v E – Operation Teddington: One of the largest criminal prosecutions ever brought in West Yorkshire, multi million pound, fraud and money laundering by defendants said by the police to have international criminal links including to the Russian ‘mafia’.


R v S & PT Ltd. Instructed to deal with confiscation orders sought both against both a company and director. Total benefit of circa £3 million reduced to circa £200,000.

R v M: Instructed to deal with confiscation in a multi-handed drugs conspiracy. Legal argument over a number of days succeeded in reducing benefit to 1/10th of that ordered in each of the other seven defendants.

R v C: Instructed to oppose an application by the Crown under s.22 POCA to revisit a confiscation order a number of years after conviction. Crown sought to increase the ‘available amount’ which would have required the family home to be sold.

R v CFS Ltd. Instructed on behalf of ‘third party’ company to apply to lift restraint order imposed pending investigation of director. Linked to proposed takeover of Doncaster Rovers FC by a consortium of overseas investors.


"Oliver is a fighter and will not accept any adverse evidence without challenging it and trying to do the best for his client. He is also a natural advocate."Legal 500, 2024
"Oliver has just got this presence in court about him and he always connects with clients and juries. He is able to present very difficult cases in the most attractive way and gets some extraordinary results."Chambers and Partners, 2024
"A fearless, polished advocate."Chambers and Partners, 2024
"Oliver is a brilliant barrister who can inspire juries to deliver positive verdicts for his clients in the most demanding cases. He is the barrister that you need on your side when you are in trouble."Legal 500, 2023
"He is well received by clients of every stripe and is extremely approachable."Chambers and Partners, 2023
"Oliver Cook has that rare combination of being both a skilled advocate and an excellent lawyer."Chambers and Partners, 2023
"A great technician who understands the more complex areas of the law such as telephone and DNA evidence."Chambers and Partners, 2022


Cook, Oliveruk-leading-juniors-2024
Instruct OliverTo instruct Oliver please contact our clerks by phone on +44 (0) 20 7036 0200 or email us at clerks@libertaschambers.com