Gary Oliver
Senior Clerk
+44 (0) 207 822 7325
Catherine Callaghan has been practising at the English Bar since 2000, and took silk in 2018. She regularly acts for the UK Government and regulatory bodies, as well as individual or corporate claimants, in the Administrative Court, Court of Appeal, and Supreme Court.
Catherine is currently the Chair of the Constitutional and Administrative Law Bar Association (ALBA). She was a member of the Attorney General’s A Panel of counsel from 2013 to 2018.
Catherine is recognised in the leading legal directories, Chambers UK and Legal 500, for her expertise in public and regulatory law, professional discipline, civil liberties & human rights, and employment law. Recent comments include:
Previous comments include:
Catherine is known for her attention to detail, her ability to construct a clear and compelling case, and to forensically deconstruct and dismantle opponents' arguments. She has an authoritative presence in court and judges trust her submissions. She has a client-focused approach, and solicitors and lay clients like her down-to-earth and approachable manner.
Catherine is a leading barrister in public and regulatory law, with a practice encompassing judicial review, statutory appeals, first instance and appellate professional disciplinary and regulatory hearings. Catherine has extensive experience representing clients in the Administrative Court, Special Immigration Appeals Commission, Court of Appeal and Supreme Court. She regularly acts for Government departments and regulatory bodies such as the General Medical Council, the Institute of Chartered Accountants in England and Wales, the Human Fertilisation and Embryology Authority, and the Advertising Standards Authority. She also acts for claimants in judicial review claims and statutory appeals against public bodies.
Catherine has developed an expertise in regulation of the tied pubs sector. She has advised and acted for Star Pubs & Bars Ltd (Heineken UK's pub estate business) and Greene King on a variety of cases concerning challenges to arbitration awards, and challenges to regulatory decisions of the Pubs Code Adjudicator.
She is a trusted adviser for a wide range of bodies on policy development, discrimination and Brexit-related issues.
Catherine is Chair of the Administrative Law Bar Association and recently coordinated ALBA's response to the government consultation on judicial review reform.
“Catherine is an expert in the field.”
Chambers and Partners, 2025
“Catherine gives excellent service on judicial review defence.”
Chambers and Partners, 2025
“She is very reassuring and always provides a great service.”
Chambers and Partners, 2023
“She is quick to distil complex facts down to the key points and arguments.”
Chambers and Partners, 2022
“An advocate of outstanding ability.”
Chambers and Partners, 2022
“Has great expertise in the field and is an excellent advocate.”
Chambers and Partners, 2021
“She's very accommodating and her command of the law is amazing.”
Chambers and Partners, 2020
“Meticulous in her preparation, she is an impressive drafter.”
Chambers and Partners, 2019
“Bright and highly impressive in professional disciplinary judicial review.”
Chambers and Partners, 2019
“Crisp, clear and persuasive; a punchy drafter and deft legal tactician.”
Legal 500, 2017
“She is incredibly easy to work with, very responsive and able to get the measure of the client.”
Chambers UK, 2016
Catherine represented the Claimant, Mr Jwanczuk, leading Tom Royston (of Garden Court North Chambers) in the High Court and Court of Appeal in a successful Article 14 discrimination challenge to the 'contribution condition' for bereavement support payment (BSP) in the Pensions Act 2014, which requires an applicant's deceased spouse or civil partner to have actually paid certain national insurance contributions during their working life.
The Court of Appeal upheld Kerr J's decision that the contribution condition violates Article 14 ECHR, read with Article 1 of the First Protocol (A1P1), because it results in denying BSP to a person whose deceased spouse or civil partner was unable to work and therefore unable to pay national insurance contributions throughout his or her working life due to disability. The High Court and Court of Appeal agreed that the Pensions Act should be read and given effect so that the contribution condition was to be treated as met if the deceased was unable to comply with it throughout their working life due to disability.
In so finding, the Court of Appeal and Kerr J agreed with the decision of the Northern Ireland Court of Appeal in O’Donnell v Department for Communities [2020] NICA 36, which had reached the same conclusion in relation to materially identical secondary legislation applicable to Northern Ireland. The decision in Jwanczuk means that the ‘principle of parity’ in social security law between different UK jurisdictions is preserved and that the content of the human rights at issue in this case are the same across the UK.
Catherine and Tom were instructed by the Public Law Project.
The Secretary of State is currently seeking permission to appeal to the Supreme Court.
Catherine acted for the Third Interested Party, Mitsubishi HC Capital UK plc, leading Simon Pritchard, in two lead cases selected by the Financial Ombudsman Service (FOS) concerning alleged mis-selling of 'fractional ownership' timeshare schemes. The Claimant finance companies (which financed consumer purchases of timeshare schemes) sought to challenge FOS's findings in these test cases that (i) the timeshare arrangements were not 'timeshare contracts' within the meaning of Regulation 7 of the Timeshare Regulations and instead were 'collective investment schemes' under s.235 FSMA; (ii) that timeshare operators had breached the Regulation 14(3) prohibition on marketing or selling a timeshare product as an investment (iii) that timeshare operators had failed to provide consumers with 'key information' in breach of the pre-contractual information requirements in the Timeshare Regulations; (iv) that standard form terms in timeshare contracts breached the requirement in Regulation 7 of the Timeshare Regulations that timeshare contracts should be expressed in plain, intelligible language; and (v) that lenders were legally responsible for the acts and omissions of timeshare operators. The Claimants succeeded in overturning some aspects of the FOS's findings, which will affect FOS decisions on outstanding consumer complaints. Catherine and Simon were instructed by Shoosmiths LLP.
Catherine acted for Star Pubs & Bars Ltd (Heineken UK's pub estate business), leading Naina Patel and Tim Johnson, in a high profile and complex statutory appeal against a £2 million penalty imposed by the Pubs Code Adjudicator, arising out of Star's alleged breaches of the Pubs Code. This was the first appeal of its kind, brought under s.58 of the Small Business, Enterprise and Employment Act 2015.
In the first of two preliminary hearings in the High Court, Morris J determined the scope of a statutory appeal under s.58(3), holding that Star was entitled to challenge the grounds for imposing a penalty (including all matters relevant to the assessment of the gravity or otherwise of the breaches of the Pubs Code), but was not entitled to challenge the findings of breach themselves. In addition, Morris J granted Star's application for disclosure of anonymous evidence given against Star by its tenants, within a confidentiality ring. A link to the judgment can be found here.
In a second preliminary hearing dealing with consequential matters, Morris J refused the PCA's application for one of the grounds of appeal, concerning procedural unfairness, to be determined as a preliminary issue. The Court was not satisfied that it would be determinative of the appeal as a whole or that it would save time and costs.
The statutory appeal was eventually settled before the substantive hearing.
Acted for the GMC in a significant statutory appeal brought by a doctor under s.40 of the Medical Act 1983, challenging a decision of the Medical Practitioners Tribunal to erase her from the medical register. The appeal raised two issues: (i) at what stage in the decision-making process is a Tribunal required to consider good character when deciding allegations of dishonesty? (ii) to what extent is a doctor's failure to tell the truth at a disciplinary hearing relevant when considering sanction?
Collins Rice J rejected the doctor's argument that the Tribunal's good character direction should have come earlier in its analysis than it did. In circumstances where the Tribunal received correct advice on good character, and summarised it accurately at the outset of its determination of facts, it could be inferred that the Tribunal took into account the doctor's good character even if it did not say so expressly before reaching conclusions on her credibility.
However, the Court upheld the doctor's appeal against sanction, finding that the Tribunal unfairly relied on the doctor's disbelieved defence when deciding sanction. This judgment attempts to resolve the tension in the case law between the doctor's right to a fair trial which includes the right to deny charges of dishonesty and the public interest in protecting patients from dishonest doctors who lack insight into their misconduct.
Catherine acted for the Independent Reviewer and the ASA (leading Tom Lowenthal) in successfully resisting a judicial review claim brought by Aldi which sought to challenge a rejection of Aldi's complaint that a Tesco's advertisement was misleading. The ASA and Independent Reviewer had decided that the Tesco ad would not mislead consumers into thinking that Tesco was price matching branded goods in its stores against Aldi own-brand goods. The JR claim was refused at the permission stage by Calver J.
Catherine acted for HM Treasury and the Home Office (leading Raymond Hill and Imogen Proud of Monckton Chambers) in successfully defending a judicial review challenge by the PSA to the consultation carried out by Treasury on public sector pension reform following the Court of Appeal's decision in McCloud, and the resulting decision to close legacy pension schemes and move members to reformed pension schemes from 1 April 2022. This case raises important constitutional issues regarding parliamentary privilege, given that the Treasury's decision was the subject of the Public Service Pensions and Judicial Offices Bill, which at that time was passing through Parliament.
Acted for the Ascension Island Government (leading Kerenza Davis and Hugh Flanagan) in successfully striking out claims brought in the Supreme Court of St Helena for malicious falsehood, misfeasance in public office, and breach of contract.
The Claimant, which operated the sole Fuel Station on Ascension Island, had brought claims against AIG for malicious falsehood, misfeasance in public office, breach of contract, and unlawful interference with economic interests, arising out of AIG’s actions in serving statutory notices on the Claimant in 2017 requiring it to address health and safety issues at the Fuel Station.
Chief Justice Charles Ekins granted AIG's strike out application, holding that the malicious falsehood claim was statute-barred and that no contract existed between the parties, so that those claims should be dismissed on a point of law under the Ascension Civil Procedure Rules. AIG also successfully argued that all of the claims should be struck out as disclosing no reasonable cause of action and as amounting to an abuse of process, in that the claims were an attempt to circumvent time limits under a statutory appeal process.
Acted for the Claimants (Heineken UK's pub estate business), leading Peter Stevenson, in a successful claim brought under s.68(2)(a) of the Arbitration Act 1996, challenging an arbitrator's award in a dispute concerning the offer of a market rent only (MRO) lease to a tied pub tenant.
Kelyn Bacon QC, sitting as a Deputy High Court judge, upheld Punch/Star's claim that the arbitrator had (1) erred in reversing the burden of proof so as to require Punch/Star to prove that a 60% stocking requirement was reasonable, when it was for the pub tenant to prove it was unreasonable; and (2) acted outside his powers under Reg 33 of the Pubs Code by ordering Punch/Star to provide an MRO lease with a 20% stocking requirement. This was a serious irregularity under s.68(2)(b) of the 1996 Act that had caused substantial injustice to the landlord and owner.
Acted for the Claimants (Heineken UK's pub estate business), leading Peter Stevenson, in the first challenge to an arbitration award made in a statutory arbitration under the Small Business, Enterprise and Employment Act 2015 and the Pubs Code Regulations 2016. The statutory scheme regulates the relationship between tied pub tenants and pub-owning businesses.
The High Court upheld the Claimants' claim that the Deputy Pubs Code Adjudicator, in her capacity as arbitrator, exceeded her statutory powers by ordering the pub landlord/owner to offer the tenant a lease with a specified minimum length. The adjudicator did not have power to order that provisions be inserted into a revised offer. This was a serious irregularity that required the award to be set aside under s.68 of the Arbitration Act 1996.
However, the High Court rejected the Claimants' claim, relying on the principle in Marcel v Commissioner of Police that documents seized by a public authority in the exercise of a statutory power could only be used for the purposes contemplated by the relevant legislation, that the adjudicator had acted unlawfully and unfairly in relying on information received in her capacity as regulator.
In 2019, Catherine provided independent written advice to the Law Commission assessing whether the Law Commission's proposed reforms to the law on leasehold enfranchisement are compatible with the Human Rights Act 1998 and in particular, the property rights protected by Article 1 of the First Protocol (A1P1). Catherine's advice, together with the Law Commission's final report, were published in January 2020. The links to the report and summary can be found here and here.
Since 2020, Catherine has been advising the Department of Levelling Up, Housing and Communities on the compatibility of its legislative proposals for leasehold reform with A1P1.
Acted for the ASA in successfully defending a judicial review challenge to the ASA’s decision that an advertisement for a CE-marked medical device was misleading and that its claims for efficacy were unsupported by adequate evidence and so breached the Committee of Advertising Practice (CAP) Code. The case established that the ASA’s approach to assessing substantiation evidence is proportionate and complies with the requirements of the Unfair Commercial Practices Directive.
Acted for the ASA (leading Ravi Mehta) in successfully defending a judicial review challenge to the ASA's decision that the word "fibre" as it is currently used in the advertising of part-fibre broadband services is not likely to mislead consumers. The proceedings were brought by the largest wholesale full-fibre provider in the UK and sought to argue that it was misleading for part-fibre broadband providers to be able to advertise their broadband services using the word “fibre”.
The case established that whether advertising claims are misleading is to be judged by reference to the average consumer of the goods and services to whom the advertising is targeted, not by reference to a consumer who is well-informed about particular features of the service such as its mechanism of delivery. The High Court held that the ASA was entitled to rely on a report commissioned to examine consumer understanding of broadband advertising claims. The report’s research sample was representative of the average consumer, and the ASA was entitled to rely on the report’s conclusions that consumers did not notice or prioritise fibre in broadband advertising and were therefore unlikely to be misled by the use of the term ‘fibre’ to describe part-fibre services.
Catherine acted for the Defendant in the first significant case to apply the reasoning in R (Belhaj) v Director of Public Prosecutions (No 1) [2018] 3 WLR 435 in relation to the meaning and scope of the phrase "criminal cause or matter" in section 18 of the Senior Courts Act 1981, the outcome of which determines whether there is a right of appeal to the Court of Appeal from a judgment of the High Court. The Court of Appeal held that the McAtee proceedings (which sought a declaration that s.31A of the Crime (Sentences) Act 1997 was incompatible with the Claimant's Article 8 rights in preventing the claimant from applying to cancel his indeterminate sentence until 10 years after release) amounted to a challenge to the sentencing regime and therefore were a criminal cause or matter in respect of which the Court of Appeal had no jurisdiction to hear the appeal.
Acted for an interested party (a defendant in criminal proceedings) in a judicial review challenge to the SFO's refusal to compel a company to disclose 'first account material' in compliance with a requirement to cooperate with the SFO under a Deferred Prosecution Agreement. The Divisional Court held that the Crown Court was the appropriate forum to resolve disputes about disclosure in criminal proceedings, but strongly criticised the SFO's approach to disclosure.
Acted for NHS Digital in a judicial review challenge to the legality of a Memorandum of Understanding between the Home Office, Department of Health and NHS Digital under which non-clinical information about migrants on the NHS database was shared with the Home Office for immigration enforcement purposes. The case settled after the defendants agreed to amend the Memorandum of Understanding.
Acted for the Defendants in a judicial review challenge to a refusal to disclose so-called Brexit 'impact analyses' under common law disclosure powers and Article 10 ECHR. The Defendants argued that requests for such information should be addressed under the Freedom of Information Act 2000.
Acted for the Solicitors Regulation Authority (SRA), intervening in an appeal to the Supreme Court on the issue whether the Employment Tribunal's jurisdiction to hear discrimination claims against professional regulatory bodies is ousted by the availability of judicial review proceedings. This turned on the issue of whether judicial review proceedings are proceedings 'in the nature of an appeal' which arise 'by virtue of an enactment' under s.120(7) of the Equality Act 2010.
Acted for the NMC successfully defending a judicial review challenge to the NMC's decision not to refer for investigation an allegation that certain nurses' entries to the register had been fraudulently procured.
Acted for the Council of the Inns of Court and the Bar Tribunal and Adjudication Service successfully defending an application for an injunction to prevent COIC & BTAS from implementing the decision of a disciplinary tribunal to disbar a barrister found guilty of dishonest conduct.
Acted for the Secretary of State (leading Christopher Staker) in successfully defending a judicial review challenge to the lawfulness of the UK Government’s conduct of its foreign relations with Ethiopia, in relation to a British citizen detained in Ethiopia. The family of the detainee sought to challenge the FCO's decision not to request his release from prison or treat his case as a kidnapping case.
Acted for the Secretary of State (led by Martin Chamberlain QC) in the First-tier Tribunal successfully resisting a challenge to a direction issued under s.128 of the Education and Skills Act 2008, which prohibited the appellant from participating in the management of independent schools on the ground that he had engaged in conduct which undermined fundamental British values. This was the first time a prohibition order of this kind has been made against a school governor.
Acted for the Secretary of State (led by James Eadie QC) in the High Court and Court of Appeal, successfully defending judicial review challenges brought by all major UK tobacco manufacturers against Parliament’s decision to adopt the Standardised Packaging of Tobacco Products Regulations 2015, which require standardised packaging for cigarettes and rolling tobacco. The tobacco manufacturers argued that the UK regulations were unlawful under international law, EU law (particularly human rights, trade mark and competition law) and domestic law. Catherine was the most senior junior in a counsel team comprising three silks and four juniors.
Acted for the HFEA (the regulator of UK fertility clinics) in the High Court and Court of Appeal, defending a high profile judicial review challenge to the regulator’s refusal to authorise export of the Claimant’s deceased daughter’s frozen eggs to enable the Claimant to receive fertility treatment in the United States. The Claimant alleged that the HFEA’s refusal amounted to a violation of her Article 8 rights to become a parent using her daughter’s gametes.
Acted for the GMC (the regulator of doctors) in successfully defending a judicial review challenge to the Registrar’s decision to close a complaint brought against the Medical Director of the NHS, Professor Sir Bruce Keogh. Concerned the proper scope of the GMC’s disciplinary powers in relation to doctors in administrative positions, following the cases of Remedy UK Ltd and Roylance.
Acted for the Secretary of State (led by James Eadie QC) in an appeal to the Supreme Court concerning the lawfulness of the Government’s schemes imposing mandatory work requirements on recipients of jobseeker’s allowance.
Catherine has a particular interest in professional disciplinary regulation in the fields of healthcare, accountancy, law, and education.
She regularly acts for the General Medical Council in judicial review proceedings and statutory appeals to the High Court from disciplinary decisions of Fitness to Practise Panels. She advises the GMC on policy development and guidance, and represented the GMC (with Robert Englehart KC) in the Public Inquiry into Mid-Staffordshire NHS Foundation Trust.
In the field of accountancy, she regularly acts for the Institute of Chartered Accountants in England and Wales (ICAEW) in internal disciplinary hearings, appeals and judicial reviews. She also acts for the Chartered Institute of Management Accountants (CIMA) and the Institute of Actuaries.
In the legal field, Catherine is a trusted adviser to the Solicitors Regulation Authority (SRA). She also advises law firms and individual solicitors on issues concerning solicitors' professional conduct and SRA reporting obligations. Catherine has been instructed as an independent investigator by a number of UK and overseas law firms to investigate misconduct by solicitors.
“She has excellent judgement and provides very clear advice.”
Chambers and Partners, 2025
“Catherine is very good. She's clever and delightful to work with.”
Chambers and Partners, 2025
“Catherine is very approachable, and she is great at getting into the detail of the case very quickly.”
Legal 500, 2025
“Catherine has a great deal of expertise; she is really knowledgeable and a good advocate.”
Chambers and Partners, 2023
“Catherine is fast, responsive and clever. She also has an innate ability to know how the SRA thinks.”
Legal 500, 2023
“Very robust, sensible and persuasive.”
Chambers and Partners, 2022
“She is so bright and diligent, excellent with clients and very hands-on.”
Chambers and Partners, 2022
“Highly proficient barrister whose broad industry expertise is widely praised.”
Chambers and Partners, 2018
“A smart and capable lawyer with total command in the fields of professional discipline and public law”
Chambers and Partners, 2017
“She has a particularly good name, and is trusted, sensible and well prepared.”
Chambers and Partners, 2016
Acted for the GMC in a significant statutory appeal brought by a doctor under s.40 of the Medical Act 1983, challenging a decision of the Medical Practitioners Tribunal to erase her from the medical register. The appeal raised two issues: (i) at what stage in the decision-making process is a Tribunal required to consider good character when deciding allegations of dishonesty? (ii) to what extent is a doctor's failure to tell the truth at a disciplinary hearing relevant when considering sanction?
Collins Rice J rejected the doctor's argument that the Tribunal's good character direction should have come earlier in its analysis than it did. In circumstances where the Tribunal received correct advice on good character, and summarised it accurately at the outset of its determination of facts, it could be inferred that the Tribunal took into account the doctor's good character even if it did not say so expressly before reaching conclusions on her credibility.
However, the Court upheld the doctor's appeal against sanction, finding that the Tribunal unfairly relied on the doctor's disbelieved defence when deciding sanction. This judgment attempts to resolve the tension in the case law between the doctor's right to a fair trial which includes the right to deny charges of dishonesty and the public interest in protecting patients from dishonest doctors who lack insight into their misconduct.
Catherine acted for the insolvency regulator, ICAEW (together with Monica Carss-Frisk QC) in a long-running professional disciplinary investigation into, and latterly, proceedings against Deloitte and three Deloitte partners (Neville Kahn, Christopher Farrington and Nicholas Edwards), arising out of their conduct as Joint Administrators and then Joint Liquidators of the high-street retail chain, Comet, which went into administration in late 2012.
The disciplinary proceedings were settled in early 2020, with Deloitte, Mr Kahn and Mr Farrington accepting liability to disciplinary action under the Institute's Disciplinary Bye-laws, together with reprimands, and a total fine of £1 million (a record fine for the Institute). Deloitte also agreed to pay the entirety of the Institute's legal costs.
Acted for the Solicitors Regulation Authority (SRA), intervening in an appeal to the Supreme Court on the issue whether the Employment Tribunal's jurisdiction to hear discrimination claims against professional regulatory bodies is ousted by the availability of judicial review proceedings. This turned on the issue of whether judicial review proceedings are proceedings 'in the nature of an appeal' which arise 'by virtue of an enactment' under s.120(7) of the Equality Act 2010.
Acted for the NMC successfully defending a judicial review challenge to the NMC's decision not to refer for investigation an allegation that certain nurses' entries to the register had been fraudulently procured.
Acted for the Council of the Inns of Court and the Bar Tribunal and Adjudication Service successfully defending an application for an injunction to prevent COIC & BTAS from implementing the decision of a disciplinary tribunal to disbar a barrister found guilty of dishonest conduct.
Acted for the GMC in the High Court and Court of Appeal, successfully defending a judicial review challenge to a refusal to restore the doctor to the medical register following voluntary erasure of her name from the register. The case concerned whether the hearing was unfair by virtue of panel members’ questioning and treatment of the doctor.
Acted for the ICAEW in disciplinary proceedings brought against an insolvency practitioner arising out of his conduct as a trustee in bankruptcy in authorising the sale of the bankrupt’s family home when he should have known that any shortfall in the property could be funded without the sale. The Disciplinary Tribunal found the charge proved and withdrew his insolvency licence for two years.
Acted for the Institute in disciplinary proceedings against an actuary for misconduct. The case raised the issue whether the Disciplinary Tribunal had jurisdiction to consider a charge of misconduct against a former member in respect of conduct occurring after his membership had ceased.
Acted for the GMC (the regulator of doctors) in successfully defending a judicial review challenge to the Registrar’s decision to close a complaint brought against the Medical Director of the NHS, Professor Sir Bruce Keogh. Concerned the proper scope of the GMC’s disciplinary powers in relation to doctors in administrative positions, following the cases of Remedy UK Ltd and Roylance.
Acted for the GMC in a judicial review claim concerning the proper construction of the GMC’s “five year rule” and the GMC’s power to reconsider a decision under that rule. The Court held that regulators have the power to review their own decisions where they are based on a fundamental mistake of fact.
Acted for CIMA in successfully resisting a judicial review challenge to a finding that an accountant was guilty of misconduct and should receive a severe reprimand and fine for making false statements in accounts that companies were exempt from statutory audit requirements.
Acted for the claimant psychotherapist in a successful judicial review challenge to the decision of the BPC to impose conditions on his registration. Settled prior to hearing.
Acted for the Institute in the High Court and Court of Appeal, successfully resisting a chartered accountant’s judicial review challenge to the Institute’s decision to find him guilty of misconduct and exclude him from membership. The case concerned the issue whether the temporary absence of a member of a disciplinary tribunal deprives the tribunal of jurisdiction to hear the complaint or amounts to a breach of natural justice capable of waiver. The decision contains important analysis on the difference between constitutive and adjudicative jurisdiction, the scope of the rule that ‘he who decides the case must hear the case’, and the legal principles concerning waiver of procedural unfairness.
Acted for the GMC in a judicial review challenge to a Fitness to Practise Panel’s decision to refuse a doctor’s application for voluntary erasure from the register.
Acted for the GMC in a 6-day statutory appeal against the GMC’s decision to erase a psychiatrist from the medical register on the basis of his inappropriate relationship with a female patient.
Acted for the Appellant (the GMC) in a successful appeal to the Court of Appeal concerning the power of the GMC’s Registrar to refer allegations about a doctor to the GMC’s Fitness to Practise Panel notwithstanding that the allegations had not been considered first by case examiners. This is an important case about the purpose and scope of the GMC (Fitness to Practise) Rules 2004.
Catherine’s civil liberties and human rights practice incorporates nationality and asylum law, national security and terrorism, and prison law. She regularly acts for the UK Government and regulatory bodies in defending decisions affecting civil liberties and human rights. Catherine also acts for police bodies, including the Metropolitan Police Service, the Metropolitan Police Authority, and Her Majesty’s Inspectorate of Constabulary.
“She has good judgement, impresses clients, is good on paper, and is good in court.”
Legal 500, 2023
“Has an authority and poise which is impressive and she is a pleasure to work with.”
Legal 500, 2019
“She has an incisive and concise style, which is hugely impressive”
Legal 500, 2016
Catherine represented the Claimant, Mr Jwanczuk, leading Tom Royston (of Garden Court North Chambers) in the High Court and Court of Appeal in a successful Article 14 discrimination challenge to the 'contribution condition' for bereavement support payment (BSP) in the Pensions Act 2014, which requires an applicant's deceased spouse or civil partner to have actually paid certain national insurance contributions during their working life.
The Court of Appeal upheld Kerr J's decision that the contribution condition violates Article 14 ECHR, read with Article 1 of the First Protocol (A1P1), because it results in denying BSP to a person whose deceased spouse or civil partner was unable to work and therefore unable to pay national insurance contributions throughout his or her working life due to disability. The High Court and Court of Appeal agreed that the Pensions Act should be read and given effect so that the contribution condition was to be treated as met if the deceased was unable to comply with it throughout their working life due to disability.
In so finding, the Court of Appeal and Kerr J agreed with the decision of the Northern Ireland Court of Appeal in O’Donnell v Department for Communities [2020] NICA 36, which had reached the same conclusion in relation to materially identical secondary legislation applicable to Northern Ireland. The decision in Jwanczuk means that the ‘principle of parity’ in social security law between different UK jurisdictions is preserved and that the content of the human rights at issue in this case are the same across the UK.
Catherine and Tom were instructed by the Public Law Project.
The Secretary of State is currently seeking permission to appeal to the Supreme Court.
Catherine is acting for the NCA (together with Andrew Bird KC and Tom Rainsbury) in opposing an application by the Second Affected Party, Mrs Hajiyeva, to stay or dismiss civil forfeiture proceedings in the Magistrates' Court brought under Part 5 of the Proceeds of Crime Act 2002. Mrs Hajiyeva seeks to argue that she and her husband, Mr Hajiyev (the former Chairman of the International Bank of Azerbaijan), cannot have a fair hearing in the forfeiture proceedings and/or that it would amount to an abuse of the court's process to hear the NCA's forfeiture application and/or a violation of their A1P1 property rights because Mr Hajiyev is currently imprisoned in Azerbaijan without direct access to English solicitors.
Catherine has acted for the Respondents (a multi-national telecoms company and its senior employees) since 2020 in an ET claim for whistleblowing detriment, disability discrimination and unfair dismissal, and also in interlocutory proceedings in the ET, the EAT and the Court of Appeal, concerning an application under Rule 50 of the ET Rules of Procedure to prohibit the disclosure of sensitive information in ET proceedings.
This is the first case to consider the scope of the ET's power to derogate from the principle of open justice where it is said to be necessary in the interests of justice and/or to protect persons' rights under Articles 3, 5, 6 or 8 ECHR and/or to protect contractual rights of confidence. It is also the first case to consider the scope of the ET's power to prohibit public disclosure of information in order to protect the safety and security of non-participants to the litigation located outside the territory of ECHR member states.
The EAT judgment is cited at [2022] ICR 1204 and the Court of Appeal judgment is cited at [2023] EWCA Civ 50; [2023] ICR 663.
In 2019, Catherine provided independent written advice to the Law Commission assessing whether the Law Commission's proposed reforms to the law on leasehold enfranchisement are compatible with the Human Rights Act 1998 and in particular, the property rights protected by Article 1 of the First Protocol (A1P1). Catherine's advice, together with the Law Commission's final report, were published in January 2020. The links to the report and summary can be found here and here.
Since 2020, Catherine has been advising the Department of Levelling Up, Housing and Communities on the compatibility of its legislative proposals for leasehold reform with A1P1.
Advised Ofsted (with Joanne Clement of 11KBW) on a judicial review claim issued by a denominational state secondary school, challenging Ofsted's decision to downgrade the school from 'outstanding' to 'inadequate'. The claim concerned the extent to which segregation in mixed sex schools constitutes unlawful sex discrimination, and the meaning and scope of the Court of Appeal decision in Al-Hijrah.
Catherine acted for the Defendant in the first significant case to apply the reasoning in R (Belhaj) v Director of Public Prosecutions (No 1) [2018] 3 WLR 435 in relation to the meaning and scope of the phrase "criminal cause or matter" in section 18 of the Senior Courts Act 1981, the outcome of which determines whether there is a right of appeal to the Court of Appeal from a judgment of the High Court. The Court of Appeal held that the McAtee proceedings (which sought a declaration that s.31A of the Crime (Sentences) Act 1997 was incompatible with the Claimant's Article 8 rights in preventing the claimant from applying to cancel his indeterminate sentence until 10 years after release) amounted to a challenge to the sentencing regime and therefore were a criminal cause or matter in respect of which the Court of Appeal had no jurisdiction to hear the appeal.
Acted for NHS Digital in a judicial review challenge to the legality of a Memorandum of Understanding between the Home Office, Department of Health and NHS Digital under which non-clinical information about migrants on the NHS database was shared with the Home Office for immigration enforcement purposes. The case settled after the defendants agreed to amend the Memorandum of Understanding.
Acted for the Secretary of State (led by Martin Chamberlain QC) in the First-tier Tribunal successfully resisting a challenge to a direction issued under s.128 of the Education and Skills Act 2008, which prohibited the appellant from participating in the management of independent schools on the ground that he had engaged in conduct which undermined fundamental British values. This was the first time a prohibition order of this kind has been made against a school governor.
Acted for the HFEA (the regulator of UK fertility clinics) in the High Court and Court of Appeal, defending a high profile judicial review challenge to the regulator’s refusal to authorise export of the Claimant’s deceased daughter’s frozen eggs to enable the Claimant to receive fertility treatment in the United States. The Claimant alleged that the HFEA’s refusal amounted to a violation of her Article 8 rights to become a parent using her daughter’s gametes.
Acted for the Secretary of State (led by Rory Phillips QC) in the Special Immigration Appeals Commission (SIAC), successfully defending the Secretary of State’s refusal to grant the applicant British citizenship. The applicant argued that the refusal constituted race discrimination under the Race Relations Act, and violated Article 14 ECHR. This was the lead test case determining SIAC’s approach to discrimination claims in naturalisation cases. Catherine was responsible for the discrimination aspects of the claim.
Acted for the Home Office (led by James Eadie QC) in an appeal to the Court of Appeal and Supreme Court concerning the scope of a litigant’s right to a fair trial and the lawfulness of the use of closed material and special advocates in the context of a discrimination claim arising out of security vetting of civil servants. The Supreme Court upheld the Home Office’s Appeal.
Acted for HM Treasury (led by James Eadie QC) in another appeal concerning the legality of closed material procedures in the context of an application by an Iranian bank to set aside an order made by HM Treasury under the Counter-Terrorism Act 2008 which directed the UK financial sector not to have any business dealings with the bank.
Catherine appears in the Employment Tribunals, the Employment Appeal Tribunal and High Court in cases involving discrimination, whistle blowing, unfair and wrongful dismissal, and redundancy. She acts for both Claimants (particularly senior managers, partners and directors) and Respondents.
Catherine is a judicial member of the Commonwealth Secretariat Arbitral Tribunal (CSAT), an international tribunal which hears contractual disputes between the Commonwealth Secretariat and its employees. She is one of 8 judicial members, chosen from around the Commonwealth, and represents the UK on the tribunal.
Catherine has been instructed as an independent investigator by a number of UK and overseas law firms to investigate potential misconduct or sexual harassment by solicitors.
Catherine co-wrote the chapter on Practice and Procedure in the textbook “Employee Competition: Covenants, Confidentiality and Garden Leave”, edited by Paul Goulding KC and first published by Oxford University Press in 2007 (2nd edition published in 2011).
“Catherine is intelligent, forthcoming and strategic.”
Chambers and Partners, 2025
“Catherine has a great deal of expertise; she is really knowledgeable and a good advocate.”
Chambers and Partners, 2023
“Highly focused on the big picture but also has the ability to retain detail – the perfect mix.”
Legal 500, 2023
“Her key strength is in her ability to provide clear, technical advice with an empathetic and supportive approach.”
Chambers and Partners, 2022
“Catherine is highly responsive and immersed in the detail of the case, which means clients feel they are in safe hands.”
Legal 500, 2022
“An extremely impressive and invaluable strategic adviser.”
Legal 500, 2022
“She's very analytical and provides wonderfully clear advice.”
Chambers and Partners, 2021
“She's fantastically good on any whistle-blowing or discrimination case.”
Chambers and Partners, 2021
“Razor sharp in her analysis and advocacy. She is wonderful with clients and I would trust her with any case.”
Legal 500, 2021
“She combines an outstanding grasp of the detail with a brilliant manner.”
Legal 500, 2018
“She is very client-friendly, very approachable and very hard-working”
Chambers and Partners, 2017
“She is extremely approachable and responsive, and has a sharp legal mind.”
Legal 500, 2016
“She grasps complex issues quickly, while delivering straightforward and client-friendly advice.”
Legal 500, 2016
Catherine has acted for the Respondents (a multi-national telecoms company and its senior employees) since 2020 in an ET claim for whistleblowing detriment, disability discrimination and unfair dismissal, and also in interlocutory proceedings in the ET, the EAT and the Court of Appeal, concerning an application under Rule 50 of the ET Rules of Procedure to prohibit the disclosure of sensitive information in ET proceedings.
This is the first case to consider the scope of the ET's power to derogate from the principle of open justice where it is said to be necessary in the interests of justice and/or to protect persons' rights under Articles 3, 5, 6 or 8 ECHR and/or to protect contractual rights of confidence. It is also the first case to consider the scope of the ET's power to prohibit public disclosure of information in order to protect the safety and security of non-participants to the litigation located outside the territory of ECHR member states.
The EAT judgment is cited at [2022] ICR 1204 and the Court of Appeal judgment is cited at [2023] EWCA Civ 50; [2023] ICR 663.
Acted for a salaried partner in a claim for sex and race discrimination against a law firm. Instructed by Farrer & Co. Settled successfully.
Acted for the FCO and British Embassy in Cairo in a claim for race discrimination, unfair dismissal and whistleblowing, brought by a former Vice Consul of the British Embassy in Cairo. The Respondents successfully argued that the ET had no territorial jurisdiction to hear the claims because of the employee's lack of connection to Great Britain, and the claims were struck out following a two-day preliminary hearing in the ET.
The ET's preliminary decision was upheld by the EAT in January 2020. The appeal concerned the scope of the exception, identified by Lord Hoffmann in Lawson v Serco, for expatriate employees who work in British social or political “enclaves”. It also considered the relevance of the fact that the claimant employee was a consular officer with immunity from local jurisdiction, who may not be able to pursue claims against the Defendants in the Egyptian courts because of state immunity.
Acted for the Solicitors Regulation Authority (SRA), intervening in an appeal to the Supreme Court on the issue whether the Employment Tribunal's jurisdiction to hear discrimination claims against professional regulatory bodies is ousted by the availability of judicial review proceedings. This turned on the issue of whether judicial review proceedings are proceedings 'in the nature of an appeal' which arise 'by virtue of an enactment' under s.120(7) of the Equality Act 2010.
Acted for the Respondent Bank in a high profile unfair dismissal, whistleblowing and bonus claim brought by a former senior executive. Catherine was brought into the case specifically to deal with a 7-day contested application by the Serious Fraud Office to hear all or part of the case in private to protect the confidentiality of the Claimant’s interview with the SFO and avoid undermining the SFO’s ongoing investigation and any future criminal proceedings. Catherine also dealt with a preliminary application by the Bank to hear part of the case in private, to protect its legal professional privilege. The applications raised the important issue of the scope of the principle of open justice and the extent to which it is appropriate to hear cases in private.
Acted for a hedge fund (led by Paul Goulding QC) in High Court litigation concerning enforceability of restrictive covenants, breach of contract, and enforceability of revocation provisions in a deferred compensation scheme.
Acted for Sumitomo in successfully striking out claims of race discrimination and victimisation.
Acted for a consultant paediatrician in an internal disciplinary hearing, and successfully defended her against a charge of dishonesty.
Catherine has a strong interest in education law, particularly in the context of public law and professional disciplinary regulation. She has acted for head teachers in professional disciplinary proceedings before the General Teaching Council, and is regularly instructed by the Department for Education and Department for Business Innovation and Skills and private education providers on a wide range of high profile education cases.
“She is a hugely able and impressive barrister; incisive written work and assured advocacy”
Legal 500, 2018
Advised Ofsted (with Joanne Clement of 11KBW) on a judicial review claim issued by a denominational state secondary school, challenging Ofsted's decision to downgrade the school from 'outstanding' to 'inadequate'. The claim concerned the extent to which segregation in mixed sex schools constitutes unlawful sex discrimination, and the meaning and scope of the Court of Appeal decision in Al-Hijrah.
Acted for the Secretary of State (led by Martin Chamberlain QC) in the First-tier Tribunal successfully resisting a challenge to a direction issued under s.128 of the Education and Skills Act 2008, which prohibited the appellant from participating in the management of independent schools on the ground that he had engaged in conduct which undermined fundamental British values. This was the first time a prohibition order of this kind has been made against a school governor.
Acted for the Secretary of State in relation to a threatened judicial review challenge to the decision to approve the expansion of the Weald of Kent Grammar School onto a satellite site in Sevenoaks. The claimant action group claimed that the proposed expansion was in fact the creation of a new grammar school, which is prohibited by legislation.
Acted for the Adjudicator in an appeal to the Court of Appeal concerning the requirement on faith schools to have regard to guidance issued by religious bodies when constructing faith-based over-subscription criteria. Settled prior to hearing.
Acted for the Secretary of State in relation to a proposed judicial review challenge to the allocation of dedicated schools grant to the Council for the 2015/16 financial year, and the calculation of top-up funding to support additional post-schools places.
Catherine regularly appears in the First-tier Tribunal, Upper Tribunal and High Court on cases concerning freedom of information.
Acted for the Defendants in a judicial review challenge to a refusal to disclose so-called Brexit 'impact analyses' under common law disclosure powers and Article 10 ECHR. The Defendants argued that requests for such information should be addressed under the Freedom of Information Act 2000.
Acted for NHS Digital in a judicial review challenge to the legality of a Memorandum of Understanding between the Home Office, Department of Health and NHS Digital under which non-clinical information about migrants on the NHS database was shared with the Home Office for immigration enforcement purposes. The case settled after the defendants agreed to amend the Memorandum of Understanding.
Acted for the MoJ in seeking to uphold the Information Commissioner's decision that information concerning the decision to establish courtesy titles of 'Lord' and 'Lady' for Justices of the Supreme Court is exempt from disclosure under s.37 of the Freedom of Information Act 2000 as relating to communications with the Sovereign or the conferring of a dignity by the Crown.
Acted for the Cabinet Office in a successful appeal to the First-tier Tribunal against the ICO's decision to require the Cabinet Office to disclose Cabinet minutes concerning the collapse of the Bank of Credit & Commerce International (BCCI) in 1991.
Acted for the Department of Health in an appeal to the First-tier Tribunal against a decision requiring DoH to disclose diaries of two senior civil servants working on private finance initiatives. The DoH argued unsuccessfully that the request was vexatious.
Catherine has a particular interest in financial services regulation. She regularly acts for and advises the Financial Conduct Authority (FCA). She has previously advised the Prudential Regulation Authority and the FCA in relation to their joint review of the failure of HBOS.
Catherine acted for the Third Interested Party, Mitsubishi HC Capital UK plc, leading Simon Pritchard, in two lead cases selected by the Financial Ombudsman Service (FOS) concerning alleged mis-selling of 'fractional ownership' timeshare schemes. The Claimant finance companies (which financed consumer purchases of timeshare schemes) sought to challenge FOS's findings in these test cases that (i) the timeshare arrangements were not 'timeshare contracts' within the meaning of Regulation 7 of the Timeshare Regulations and instead were 'collective investment schemes' under s.235 FSMA; (ii) that timeshare operators had breached the Regulation 14(3) prohibition on marketing or selling a timeshare product as an investment (iii) that timeshare operators had failed to provide consumers with 'key information' in breach of the pre-contractual information requirements in the Timeshare Regulations; (iv) that standard form terms in timeshare contracts breached the requirement in Regulation 7 of the Timeshare Regulations that timeshare contracts should be expressed in plain, intelligible language; and (v) that lenders were legally responsible for the acts and omissions of timeshare operators. The Claimants succeeded in overturning some aspects of the FOS's findings, which will affect FOS decisions on outstanding consumer complaints. Catherine and Simon were instructed by Shoosmiths LLP.
Represented the FCA before the Regulatory Decisions Committee, and successfully obtained a prohibition order against Carlo Palombo on the basis that he is not a fit and proper person to perform functions in relation to regulated activities. Mr Palombo was one of several Barclays employees convicted of conspiracy to defraud in respect of fixing EURIBOR rates.
Represented the FCA before the Regulatory Decisions Committee in a case concerning a Hong Kong-based premium listed company’s failure to disclose inside information concerning a downturn in its expected profits in a timely manner. The RDC held that the company and two of its directors breached the FCA’s Disclosure and Transparency Rules and Premium Listing Principles. The RDC imposed a fine of £411,000 on the company, £214,300 on its CEO and £40,200 on its FD.
In March 2019, HM Treasury published the findings of the independent review of the prudential supervision of The Co-operative Bank plc between 2008 and 2013. The independent review was carried out by Mark Zelmer (a former senior official at the Bank of Canada). The report makes detailed recommendations for the Prudential Regulation Authority and Bank of England relating to supervisory policy and practice.
Catherine was engaged (with Hollie Higgins) to provide independent legal advice to the independent reviewer on all public law issues relating to the preparation of his report, including in relation to ‘Maxwellisation’ of persons criticised in his report.
BA, LLB (Hons) (Victoria University of Wellington); LLM (Cambridge)
Catherine first qualified as a barrister and solicitor in New Zealand and worked in the commercial litigation department of the New Zealand law firm Rudd Watts & Stone (now Minter Ellison Rudd Watts). After being ranked 1st in her year in the LLM at the University of Cambridge, she worked as a solicitor in the London office of Clifford Chance from 1997 to 1999, practising in public international law.
Catherine’s experience as a solicitor in two jurisdictions has given her an invaluable understanding and appreciation of working as part of an integrated team with solicitors and clients.
In 2007, Catherine taught public law and comparative human rights law at Victoria University of Wellington in New Zealand. She also spent two months working as Crown Counsel for the Crown Law Office in Wellington, where she advised the New Zealand Government on a variety of public law matters.
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