header-logo header-logo

Home Login E-newsletter About us
14 March 2019 / Simon Parsons
Issue: 7832 / Categories: Features , Procedure & practice , Judicial review
printer mail-detail

Challenging the balance of power (Pt 2)

© Copyright LexisNexis 2026. All Rights Reserved.

In his second update, Simon Parsons examines the possible grounds to challenge the public law decisions taken by public bodies
  • Grounds of judicial review: illegality, irrationality, procedural impropriety.

See 'Challenging the balance of power (Pt 1)' here

Decisions of public bodies are liable to challenge by way of judicial review and may be quashed as ultra vires (beyond the powers) by reference to the ordinary principles of English public law. The jurisdiction of the court is supervisory and not appellate thus judicial review looks at legality, not merits (the quality of the decision) it cannot (supposedly) provide the applicant with a substitute decision as the decision is for government.

Substantive hearing stage

In Council of Civil Service Unions v Minister for the Civil Service [1985] A C 374 HL (the GCHQ case) Lord Diplock identified (at 410-411) three grounds of judicial review as: 

  • Illegality -where a public body abuses its power. (Substantive ultra vires).
  • Irrationality -unreasonableness- a decision that defies logic- a decision
    • If you are not a subscriber, subscribe now to read this content
    If you are already a subscriber sign in
    ...or Register for two weeks' free access to subscriber content

    MOVERS & SHAKERS

    Read All
    Sponsored by
    Zylpha LogoClick to know more
    Thomson Hayton Winkley—Jordan Wallace

    Thomson Hayton Winkley—Jordan Wallace

    Thomson Hayton Winkley strengthens family law team

    Ward Hadaway—Barnaby Rosenthall

    Ward Hadaway—Barnaby Rosenthall

    Construction lawyer returns to Ward Hadaway in Teesside role

    Bird & Bird—Shahin Baghaei

    Bird & Bird—Shahin Baghaei

    Bird Bird hires leading legal transformation expert

    NEWS
    Read All
    SRA sounds warning over AI misuse as reports & investigations mount
    The Solicitors Regulation Authority (SRA) has warned solicitors and law firms that using artificial intelligence does not alter their professional obligations, amid concerns over inaccurate legal material and client confidentiality
    NLJ this week Civil way: Practical procedure lessons & cautionary tales
    From forgotten interest claims to case-management appeals, a string of procedural developments offers useful—and occasionally cautionary—lessons for practitioners
    NLJ this week: Fraud in the digital age

    Jonathan Fisher KC highlights that it now accounts for around 40% of criminal offences, with roughly 70% involving technology, and argues that the UK cannot simply prosecute its way out of the problem. Detection, investigation and prosecution all require improvement, while different fraud types demand tailored responses.

    NLJ this week: Right outcome, troubling reasoning?
    How forcefully can a litigant criticise a public authority before robust advocacy crosses the line into unreasonable conduct? 
    NLJ this week: Love, money & the spreadsheet
    Can a meticulously maintained spreadsheet turn a couple’s informal financial arrangements into legally enforceable obligations? 
    Copyright © 2026 LexisNexis
    back-to-top-scroll