¹ See e.g. Allan, T.R.S., “Doctrine and Theory in Administrative Law: An Elusive Quest for the Limits of Jurisdiction” [2003] P.L. 429 Google Scholar; Craig, P., Administrative Law, 7th ed. (London 2012), 476–80Google Scholar; Taggart, M., “The Contribution of Lord Cooke to Scope of Review Doctrine in Administrative Law: A Comparative Common Law Perspective” in Rishworth, P. (ed.), The Struggle for Simplicity in the Law: Essays in Honour of Lord Cooke of Thorndon (Wellington 1997), 213Google Scholar; Williams, R., “When Is an Error Not an Error? Reform of Jurisdictional Review of Error of Law and Fact” [2007] P.L. 793 Google Scholar; Lewans, M., Administrative Law and Judicial Deference (Oxford 2016), 44–45 Google Scholar; Arvind, T.T. and Stirton, L., “The Curious Origins of Judicial Review” (2017) 133 L.Q.R. 91 Google Scholar, at 96.

² Forsyth, C., “Showing the Fly the Way Out of the Flybottle: The Value of Formalism and Conceptual Reasoning in Administrative Law” [2007] C.L.J. 325 CrossRefGoogle Scholar. On the distinction between formal and substantive reasoning, see Atiyah, P.S. and Summers, R.S., Form and Substance in Anglo-American Law (Oxford 1987)Google Scholar.

³ The classic on the requirement for legal authority is Entick v Carrington (1765) 19 St. Tr. 1029, 1066. For discussion of this case and its significance, see Tomkins, A. and Scott, P. (eds.), Entick v Carrington: 250 Years of the Rule of Law (Oxford 2015)Google Scholar.

⁴ It might seem dubious to claim that judges are among the “subjects” of administrative authorities, but the account of legitimate authority defended in this article makes that claim more plausible. The courts are subjects of administrative authorities when the latter has a greater claim to legitimate authority than the former.

⁵ Cf. Huang v Secretary of State for the Home Department [2007] UKHL 11; [2007] 2 A.C. 167, at [16], per Lord Bingham of Cornhill.

⁶ Associated Provincial Picture Houses v Wednesbury Corporation [1948] 1 K.B. 223 (CA). As we shall see in Section V below, Lord Greene and many others have treated reasonableness review as a test for jurisdiction.

⁷ See Wilberg, H. and Elliott, M. (eds), The Scope and Intensity of Substantive Review: Traversing Taggart's Rainbow (Oxford 2015)Google Scholar.

⁸ Gardner, J., “The Many Faces of the Reasonable Person” (2015) 131 L.Q.R. 563 Google Scholar, at 566–67. See also MacCormick, N., “Reasonableness and Objectivity” (1999) 74 Notre Dame L.Rev. 1575 Google Scholar; Gardner, J., “The Mysterious Case of the Reasonable Person” (2001) 51 U.T.L.J. 273 CrossRefGoogle Scholar.

⁹ The failure to understand this point about legitimate authority is the central flaw in Matthew Lewans's defence on judicial deference on the basis of the legitimate authority of the administrative agency: see e.g. Lewans, Administrative Law and Judicial Deference, p. 13: “[J]udges should respect or defer to administrative decisions which are fair and reasonable, instead of substituting their interpretation of the law when it deviates from the substance of an administrative decision.”

¹⁰ R. (Corner House Research) v Director of the Serious Fraud Office [2008] EWHC 714 (Admin); [2009] 1 A.C. 756; R. (Corner House Research) v Director of the Serious Fraud Office [2008] UKHL 60; [2009] 1 A.C. 756.

¹¹ Criminal Justice Act 1987, s. 1(3): “The Director may investigate any suspected offence which appears to him on reasonable grounds to involve serious or complex fraud.”

¹² Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [50]–[53]. See also R. (Bermingham) v Director of the Serious Fraud Office [2006] EWHC 200; [2007] Q.B. 727, at [64], per Laws L.J.: “it will take a wholly exceptional case on its legal merits to justify a judicial review of a discretionary decision by the Director to investigate or not.”

¹³ Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [53].

¹⁴ Ibid., at [54], citing Huang [2007] UKHL 11; [2007] 2 A.C. 167, at [16], per Lord Bingham of Cornhill.

¹⁵ Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [56]–[59].

¹⁶ Ibid., at [59].

¹⁷ Ibid., at [67].

¹⁸ Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [83]. See also R. v Coventry City Council, ex parte Phoenix Aviation [1995] 3 All E.R. 37, 62, per Simon Brown L.J. (emphasis added): “Tempting though it may be for public authorities to yield too readily to threats of disruption, they must expect the courts to review any such decision with particular rigour … As when fundamental human rights are in play, the courts will adopt a more interventionist role.” Simon Brown L.J. went on to decide Corner House in the House of Lords, and distinguished this case: see [2008] UKHL 60, at [58], per Lord Brown of Eaton-under-Heywood.

¹⁹ Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [91]–[93].

²⁰ Ibid., at [98].

²¹ Ibid., at [80]–[86], [170]. Moses L.J. believed that one alternative would have been “to explain that the attempt to halt the investigation by making threats could not, by law, succeed”: para. [101]. But that was not correct on Moses L.J.’s own view of the law. On that view, the threat would have succeeded if the Saudis could not be dissuaded from pursuing the threat.

²² Corner House [2008] EWHC 714 (Admin); [2009] 1 A.C. 756, at [55].

²³ Ibid., at [100]: noting that it suited the Government's commercial and diplomatic interests to stop the investigation, Moses L.J. suggested that “too ready a submission may give rise to the suspicion that the threat was not the real ground for the decision at all; rather it was a useful pretext”.

²⁴ Ibid., at [54].

²⁵ Corner House [2008] UKHL 60, at [38].

²⁶ Ibid., at [38].

²⁷ Ibid., at [52]–[53].

²⁸ Corner House [2008] UKHL 60, at [58], per Lord Brown of Eaton-under-Heywood, distinguishing his judgment in Phoenix Aviation [1995] 3 All E.R. 37, at 62, which was relied on by the Divisional Court: see note 18 above.

²⁹ Corner House [2008] UKHL 60, at [41].

³⁰ See Raz, J., “The Rule of Law and Its Virtue” in Raz, J. (ed.), The Authority of Law: Essays on Law and Morality (Oxford 1979)CrossRefGoogle Scholar. See further Craig, P., “Formal and Substantive Conceptions of the Rule of Law: An Analytical Framework” [1997] P.L. 467 Google Scholar; Grant, J.A., “The Ideals of the Rule of Law” (2017) 37 O.J.L.S. 383 Google Scholar.

³¹ Remarkably, even studies offering a theory of deference in administrative law (e.g. Daly, P., A Theory of Deference in Administrative Law (Cambridge 2012)CrossRefGoogle Scholar) are written without any reference to Raz's theory. A recent exception is Matthew Lewans; however, Lewans rejects Raz's arguments on the basis of misunderstandings about those arguments, as I discuss below. This misunderstanding is also demonstrated in the distinction he draws between jurisdiction and legitimate authority: see e.g. Lewans, Administrative Law and Judicial Deference, p. 2: “instead of focusing our attention on jurisdictional parameters, we should ask more directly whether administrative officials have legitimate authority to interpret the law”.

³² J. Raz, “Legitimate Authority” in Raz, The Authority of Law, p. 3.

³³ Raz, J., The Morality of Freedom (Oxford 1986), 47Google Scholar. See also Raz, J., “Authority, Law and Morality” in Raz, J. (ed.), Ethics in the Public Domain: Essays in the Morality of Law and Politics, rev. ed. (Oxford 1994), 214Google Scholar.

³⁴ Corner House [2008] UKHL 60, at [53], per Baroness Hale of Richmond.

³⁵ On values and interests, see Macklem, T. and Gardner, J., “Value, Interest, and Well-Being” (2006) 18 Utilitas 362 CrossRefGoogle Scholar.

³⁶ Raz, “Authority, Law and Morality”, p. 214. See also Raz, The Morality of Freedom, p. 53.

³⁷ This objection is made by, e.g. J Waldron, ., “Authority for Officials” in Meyer, L.H., Paulson, S.L. and Pogge, T.W. (eds.), Rights, Culture and the Law: Themes from the Legal and Political Philosophy of Joseph Raz (Oxford 2003), 64–69 Google Scholar; Hershovitz, S., “Legitimacy, Democracy, and Razian Authority” (2003) 9 LEG 201, 218–19Google Scholar; Besson, S., “Democracy, Law and Authority” (2005) 2 Journal of Moral Philosophy 89 CrossRefGoogle Scholar. This objection is also adopted in Lewans, Administrative Law and Judicial Deference, pp. 194–95.

³⁸ For a defence of this conclusion, see Macklem, T., Law and Life in Common (Oxford 2015), 114–15Google Scholar.

³⁹ Raz, J., “The Problem of Authority: Revisiting the Service Conception” in Raz, J. (ed.), Between Authority and Interpretation: On the Theory of Law and Practical Reason (Oxford 2009), 153 CrossRefGoogle Scholar.

⁴⁰ Hershovitz, S., “The Role of Authority” (2011) 7 Philosophers’ Imprint 1, 5 Google Scholar.

⁴¹ Raz, The Morality of Freedom, p. 46. See also Raz, “Authority, Law and Morality”, p. 214.

⁴² Raz, The Morality of Freedom, pp. 47–48.

⁴³ Raz, J., Practical Reason and Norms ([1975], Oxford 1999), 46CrossRefGoogle Scholar.

⁴⁴ Raz sometimes describes the excluded reasons as the “conflicting reasons … that the law-maker was meant to consider before issuing the directive”: Raz, “The Problem of Authority”, p. 144, emphasis added. Two points are worth raising: first, the idea that the excluded reasons are only conflicting reasons is contestable; and secondly, the excluded reasons are perhaps better described as those the authority was meant to settle, which may be narrower than those it was meant to consider. See further Perry, S., “Political Authority and Political Obligation” in Green, L. and Leiter, B. (eds.), Oxford Studies in Philosophy of Law: Volume 2 (Oxford 2013), 45Google Scholar.

⁴⁵ Raz, The Morality of Freedom, p. 46.

⁴⁶ Jowell, J., “Caving In: Threats and the Rule of Law” [2008] J.R. 273, 275–76Google Scholar.

⁴⁷ Raz, J., “On Respect, Authority, and Neutrality: A Response” (2010) 120 Ethics 279, 298CrossRefGoogle Scholar.

⁴⁸ See e.g. Perry, S.R., “Second-Order Reasons, Uncertainty and Legal Theory” (1989) 62 S.Cal.L.Rev. 913 Google Scholar; Schauer, F., Playing by the Rules: A Philosophical Examination of Rule-Based Decision-Making in Law and in Life (Oxford 1991), 88–93 Google Scholar.

⁴⁹ See Grant, J., “The Scales of Authority” (2015) 60 Am.J.Juris. 79 CrossRefGoogle Scholar, at 85–87. Raz draws a similar, though different, conclusion – and for different reasons – when he writes that the cases for conformity with reason and for deciding oneself “may be incommensurate, with the (uncomfortable) result that whether one is then subject to authority is undetermined”: Raz, “The Problem of Authority”, p. 139.

⁵⁰ Raz, The Morality of Freedom, p. 61.

⁵¹ Ibid., at p. 61.

⁵² Ibid., at p. 62.

⁵³ Ibid., at p. 62.

⁵⁴ Ibid., at p. 62.

⁵⁵ See e.g. Martin, M., Judging Positivism (Oxford 2014), 83Google Scholar; Lewans, Administrative Law and Judicial Deference, p. 212.

⁵⁶ Lewans, Administrative Law and Judicial Deference, p. 212.

⁵⁷ Raz, The Morality of Freedom, p. 62.

⁵⁸ Raz, “Authority, Law and Morality”, p. 219.

⁵⁹ Hurd, H., “Challenging Authority” (1991) 100 Yale L.J. 1611 CrossRefGoogle Scholar, at 1634. A similar point is made in Kyritsis, D., “The Persistent Significance of Jurisdiction” (2012) 25 Ratio Juris 343 CrossRefGoogle Scholar, at 348.

⁶⁰ Raz suggests that the pre-emption thesis does not debar people from criticising the authority “for having ignored certain reasons or for having been mistaken about their significance”; the pre-emption thesis merely entails that “action for some of these reasons … is excluded”: Raz, The Morality of Freedom, p. 42. Cf. CREEDNZ Inc. v Governor General [1981] 1 N.Z.L.R. 172, 183, per Cooke J., suggesting that the courts should defer to a decision maker's reasonable judgment as to the relevance of a consideration.

⁶¹ See Endicott, T., Administrative Law, 3rd ed. (Oxford 2015), 280–85CrossRefGoogle Scholar; H. Wilberg, “Deference on Relevance and Purpose? Wrestling with the Law/Discretion Divide” in Wilberg and Elliott (eds.), The Scope.

⁶² Jowell, “Caving In”, p. 276.

⁶³ R. (ProLife Alliance) v British Broadcasting Corporation [2003] UKHL 23; [2004] 1 A.C. 185, 240, per Lord Hoffmann.

⁶⁴ Steyn, Lord, “Deference: A Tangled Story” [2005] P.L. 346 Google Scholar, at 350.

⁶⁵ See e.g. Dyzenhaus, D., “The Politics of Deference: Judicial Review and Democracy” in Taggart, M. (ed.), The Province of Administrative Law (Oxford 1997)Google Scholar; Hunt, M., “Sovereignty's Blight” in Bamforth, N. and Leyland, P. (eds.), Public Law in a Multi-Layered Constitution (Oxford 2003)Google Scholar.

⁶⁶ Endicott, T., “Comity among Authorities” (2015) 68 C.L.P. 1 Google Scholar, at 4.

⁶⁷ Ibid., pp. 9–11, 22–24.

⁶⁸ Ibid., p. 5.

⁶⁹ For a defence of the term “UK administrative law”, see Craig, P., UK, EU and Global Administrative Law: Foundations and Challenges (Cambridge 2015), 10CrossRefGoogle Scholar. Scots law eventually followed the English position on error of law in Eba v Advocate General for Scotland [2011] UKSC 29; [2012] 1 A.C. 710, at [34], per Lord Hope of Craighead. For the position in Northern Ireland, see Anthony, G., Judicial Review in Northern Ireland, 2nd ed. (Oxford 2014), ch. 5Google Scholar.

⁷⁰ See Craig, P., “Judicial Review of Questions of Law: A Comparative Perspective” in Rose-Ackerman, S. and Lindseth, P.L. (eds.), Comparative Administrative Law (Cheltenham 2010)Google Scholar; Cane, P., Controlling Administrative Power: An Historical Comparison (Cambridge 2016), 215–37CrossRefGoogle Scholar.

⁷¹ See Rubinstein, A., Jurisdiction and Illegality (Oxford 1965)Google Scholar; Craig, Administrative Law, pp. 477–78. For defences of the old approach, exemplified by R. v Bolton (1841) 1 Q.B. 66; see Gordon, D.M., “The Relation of Facts to Jurisdiction” (1929) 45 L.Q.R. 459 Google Scholar, and his articles at (1931) 47 L.Q.R. 386, (1939) 55 L.Q.R. 521, (1951) 67 L.Q.R. 452, (1966) 82 L.Q.R. 515 and (1971) 34 M.L.R. 1. See also Murray, P., “Escaping the Wilderness: R. v Bolton and Judicial Review for Error of Law” [2016] C.L.J. 333 CrossRefGoogle Scholar.

⁷² Anisminic v Foreign Compensation Commission [1969] 2 A.C. 147 (HL). See Feldman, D., “ Anisminic in Perspective” in Juss, S. and Sunkin, M. (eds.), Landmark Cases in Public Law (Oxford 2017)Google Scholar.

⁷³ In Re Racal Communications Ltd. [1981] A.C. 374 (HL), 382–83, per Lord Diplock.

⁷⁴ The majority in Anisminic did not abandon the distinction between jurisdictional and non-jurisdictional errors of law: see Anisminic [1969] 2 A.C. 147, 174, per Lord Reid, 195, per Lord Pearce, 209, per Lord Wilberforce. See further Endicott, Administrative Law, pp. 321–23.

⁷⁵ R. v Hull University Visitor, ex parte Page [1993] A.C. 682 (HL), 702, per Lord Browne-Wilkinson.

⁷⁶ Hare, I., “The Separation of Powers and Judicial Review for Error of Law” in Forsyth, C. and Hare, I. (eds.), The Golden Metwand and the Crooked Cord: Essays on Public Law in Honour of Sir William Wade (Oxford 1998)Google Scholar.

⁷⁷ For examples of exceptions to the general rule, see Page [1993] A.C. 682, 702–3, per Lord Browne-Wilkinson (a special type of law of which the university visitor was the final arbiter); Racal [1981] A.C. 374, 383, per Lord Diplock; Page [1993] A.C. 682, 703, per Lord Browne-Wilkinson (an inferior court made “final and conclusive” by statute); R. (Cart) v The Upper Tribunal [2011] UKSC 28; [2012] 1 A.C. 663, at [57], per Baroness Hale of Richmond (Upper Tribunal decisions, reviewed only when it would be “rational and proportionate” to do so).

⁷⁸ Hare, “The Separation”, p. 120.

⁷⁹ See Allan, “Doctrine and Theory”, pp. 443–45; Endicott, Administrative Law, pp. 330–31.

⁸⁰ See e.g. Beatson, J., “The Scope of Judicial Review for Error of Law” (1984) 4 O.J.L.S. 22 CrossRefGoogle Scholar.

⁸¹ Craig, Administrative Law, p. 500.

⁸² Ibid., p. 487. See also Taggart, “The Contribution of Lord Cooke”.

⁸³ See e.g. Hare, “The Separation”, p. 131; Hamburg, P., Is Administrative Law Unlawful (Chicago 2014)CrossRefGoogle Scholar.

⁸⁴ Beatson, “The Scope”, pp. 41–42. See further Endicott, Administrative Law, ch. 9.

⁸⁵ The classic example of this approach is Lord Radcliffe's speech in Edwards v Bairstow [1956] A.C. 14, 33–36. For a good illustration, see R. v Monopolies and Mergers Commission, ex parte South Yorkshire Transport Ltd. [1993] 1 W.L.R. 23 (HL), 30–32, per Lord Mustill. See further Endicott, T.A.O., “Questions of Law” (1998) 114 L.Q.R. 292 Google Scholar, at 306, 316–21; Williams, “When Is an Error Not an Error?”, pp. 803–08.

⁸⁶ Cooper v Wandsworth Board of Works (1863) 14 C.B.N.S. 180, 194, per Byles J.: “Although there are no positive words in a statute requiring that the party shall be heard, yet the justice of the common law shall supply the omission of the legislature.”

⁸⁷ See e.g. Forsyth, C., “Of Fig Leaves and Fairy Tales: The Ultra Vires Doctrine, the Sovereignty of Parliament and Judicial Review” [1996] C.L.J. 122 CrossRefGoogle Scholar, at 133: “what an all powerful Parliament does not prohibit, it must authorise either expressly or impliedly. … There is no grey area between authorisation and prohibition or between empowerment and the denial of power.” See also Elliott, M., The Constitutional Foundations of Judicial Review (Oxford 2001), ch. 4Google Scholar.

⁸⁸ See e.g. Laws, J., “Illegality: The Problem of Jurisdiction” in Supperstone, M. and Goudie, J. (eds.), Judicial Review (London 1997)Google Scholar, paras. 4.17–4.18; Halpin, A., “The Theoretical Controversy Concerning Judicial Review” (2001) 64 M.L.R. 500 CrossRefGoogle Scholar; Endicott, T., “Constitutional Logic” (2003) 53 U.T.L.J. 201 CrossRefGoogle Scholar, at 204–05, 213–16; Craig, UK, EU and Global Administrative Law, pp. 138–40.

⁸⁹ See further Endicott, T., “Legal Interpretation” in Marmor, A. (ed.), The Routledge Companion to Philosophy of Law (London 2012), 119–20Google Scholar.

⁹⁰ For a good and succinct summary of these factors, see Endicott, Administrative Law, pp. 328–29.

⁹¹ R. v Secretary of State for Foreign and Commonwealth Affairs, ex parte World Development Movement Ltd. [1995] 1 W.L.R. 386 (DC).

⁹² Ibid., at p. 401, per Rose L.J.

⁹³ See e.g. Lord Irvine of Lairg, “Judges and Decision Makers: The Theory and Practice of Wednesbury Review” [1996] P.L. 59, at 69; Sumption, J., “Judicial and Political Decision-Making: The Uncertain Boundary” [2011] J.R. 301 Google Scholar, at 305–06.

⁹⁴ Chevron USA Inc. v Natural Resources Defense Council 467 US 837, 842–43 (1984).

⁹⁵ National Cable & Telecommunications Association v Brand X Internet Services 125 S. Ct 2688, 2712 (2005), per Breyer J. Statutory ambiguity is not the only justification for deference given by the US courts, which also discuss other reasons, including expertise and political accountability: see Chevron 467 US 837, 844, 865; United States v Mead Corporation 533 US 218, 227–31 (2001); Barnhart v Walton 535 US 212, 222 (2002).

⁹⁶ See the reassessment of the law in Dunsmuir v New Brunswick 2008 SCC 9; [2008] 1 S.C.R. 190.

⁹⁷ For the list of factors, see Pushpanathan v Canada (Minister of Citizenship and Immigration) [1998] 1 S.C.R. 982. Confusingly, the Supreme Court of Canada later held that the pragmatic and functional was not necessary when determining “true questions of jurisdiction or vires”: Dunsmuir [2008] 1 S.C.R. 190, at [59], per Bastarache J. and LeBel J. For criticism and doubts about this category, see Craig, “Judicial Review of Questions of Law”, p. 460; Alberta (Information and Privacy Commissioner) v Alberta Teachers’ Association, 2011 S.C.C. 61; [2011] 3 S.C.R. 654, at [42], per Rothstein J.

⁹⁸ Cf. Endicott, “Comity among Authorities”.

⁹⁹ The Supreme Court of Canada used to draw a distinction between unreasonableness and “patent unreasonableness”, which roughly captured this point: see Canadian Union of Public Employees Local 963 v New Brunswick Liquor Co. [1979] 2 S.C.R. 227, per Dickson J.

¹⁰⁰ R. v Secretary of State for the Home Department, ex parte Brind [1991] 1 A.C. 696 (HL), 748, per Lord Bridge of Harwich, 761, per Lord Ackner. Cf. R. v Secretary of State for the Home Department, ex parte Simms [2000] 2 A.C. 115, 130, per Lord Steyn, holding that “the principle of legality” is a presumption of statutory interpretation “even in the absence of an ambiguity”.

¹⁰¹ Endicott, “Constitutional Logic”, pp. 214–15.

¹⁰² See Bromley London Borough Council v Greater London Council [1983] 1 A.C. 768 (HL), 821, per Lord Diplock: “Powers … although unqualified by any express words in the Act, may nonetheless be subject to implied limitations… [T]he question of discretion is, in my view, inseparable from the question of construction.”

¹⁰³ See e.g. Feldman, D., “Error of Law and Flawed Administrative Acts” [2014] C.L.J. 275 CrossRefGoogle Scholar, at 288–89, 312–13, citing Robinson v Secretary of State for Northern Ireland [2002] UKHL 32; [2002] N.I. 390; Wang v Commissioners of Inland Revenue [1994] 1 W.L.R. 1286 (PC), 1296, per Lord Slynn of Hadley.

¹⁰⁴ See e.g. Allan, T.R.S., The Sovereignty of Law: Freedom, Constitution, and Common Law (Oxford 2013), 112CrossRefGoogle Scholar: “A public official acts ultra vires – in excess of jurisdiction – if he … acts unreasonably”; Elliott, M., “The Ultra Vires Doctrine in a Constitutional Setting: Still the Central Principle of Administrative Law” [2000] C.L.J. 129 Google Scholar, at 135: “logic dictates that any requirements of fairness and rationality which obtain must be internal to the grant [of executive power] itself.”

¹⁰⁵ Wednesbury [1948] 1 K.B. 223, 231 and 234, per Lord Greene M.R.

¹⁰⁶ Ibid.

¹⁰⁷ Secretary of State for Education and Science v Tameside Metropolitan Borough Council [1977] A.C. 1014 (HL), 1064, per Lord Diplock.

¹⁰⁸ Gardner, “The Many Faces”, pp. 566–67.

¹⁰⁹ Wednesbury [1948] 1 K.B. 223, 230, per Lord Greene M.R.

¹¹⁰ R. (Daly) v Secretary of State for the Home Department [2001] UKHL 26; [2001] 2 A.C. 532, at [32], per Lord Cooke of Thorndon.

¹¹¹ Lord Cooke of Thorndon, “The Discretionary Heart of Administrative Law” in Forsyth and Hare (eds.), The Golden Metwand, p. 128.

¹¹² R. v Chief Constable of Sussex, ex parte International Trader's Ferry Ltd. [1999] 2 A.C. 418, 452–53, per Lord Cooke of Thorndon.

¹¹³ This approach to reasonableness is not unique to judicial review: for example, in using the concept of reasonableness in negligence claims, the courts also show deference to experts. See Hickman, T.R., “The Reasonableness Principle: Reassessing its Place in the Public Sphere” [2004] C.L.J. 166 CrossRefGoogle Scholar, at 178–81; Woolf, Lord, “Are the Courts Excessively Deferential to the Medical Profession?” (2001) 9 Med.L.R. 1 Google ScholarPubMed, at 1–2.

¹¹⁴ Sir J. Laws, “Wednesbury” in Forsyth and Hare (eds), The Golden Metwand, p. 190: “The rule of reason requires a variable standard of review.”

¹¹⁵ Ibid., pp. 196–97; P. Craig, “The Nature of Reasonableness Review” (2013) 66 C.L.P. 131; Craig, UK, EU and Global Administrative Law, p. 258. Cf. Sir Sales, Philip, “Rationality, Proportionality and the Development of the Law” (2013) 129 L.Q.R. 223 Google Scholar, 236.

¹¹⁶ See Rivers, J., “Proportionality and Variable Intensity of Review” (2006) 65 C.L.J. 174 CrossRefGoogle Scholar, at 201; Irvine, “Judges and Decision Makers”, p. 65. Cf. Daly [2001] UKHL 26; [2001] 2 A.C. 532, at [27], per Lord Steyn: “the doctrine of proportionality may require the reviewing court to assess the balance which the decision-maker has struck, not merely whether it is within the range of rational or reasonable decisions”. This explanation of the difference was also expressed in Smith and Grady v UK (1999) 29 EHRR 493.

¹¹⁷ R. v Secretary of State for the Home Department, ex parte Brind [1991] 1 A.C. 696, 762–63, per Lord Ackner.

¹¹⁸ For this claim, see Taggart, M., “Proportionality, Deference, Wednesbury ” [2008] N.Z.L.Rev. 423 Google Scholar, at 439–40, 465.

¹¹⁹ This is the best justification for the use of “anxious scrutiny” in English law in cases involving fundamental rights: see e.g. Bugdaycay v Secretary of State for the Home Department [1987] A.C. 514; R. v Ministry of Defence, ex parte Smith [1996] Q.B. 517, 554, per Sir Thomas Bingham M.R. Compare M. Elliott, “From Bifurcation to Calibration: Twin-Track Deference and the Culture of Justification” in Wilberg and Elliott (eds.), The Scope.

¹²⁰ See e.g. R. v Secretary of State for the Environment, ex parte Nottinghamshire County Council [1986] A.C. 240.

¹²¹ Huang [2007] UKHL 11; [2007] 2 A.C. 167, at [16], per Lord Bingham of Cornhill.

¹²² Allan, The Sovereignty of Law, p. 277. See also Allan, T.R.S., “Human Rights and Judicial Review: A Critique of ‘Due Deference’” [2006] C.L.J. 671 CrossRefGoogle Scholar, at 688. For defences of the notion of due deference, see Hunt, “Sovereignty's Blight”; Young, A.L., “In Defence of Due Deference” (2009) 72 M.L.R. 554 CrossRefGoogle Scholar; Kavanagh, A., “Defending Deference in Public Law and Constitutional Theory” (2010) 126 L.Q.R. 222 Google Scholar.

¹²³ Allan, The Sovereignty of Law, pp. 277–78; Allan, “Human Rights and Judicial Review”, p. 688; Allan, T.R.S., “Judicial Deference and Judicial Review: Legal Doctrine and Legal Theory” (2011) 127 L.Q.R. 96 Google Scholar, at 100–01.

¹²⁴ Allan, The Sovereignty of Law, pp. 277–78; Allan, “Human Rights and Judicial Review”, pp. 690–91.

¹²⁵ Allan, “Human Rights and Judicial Review”, p. 694. See also Allan, The Sovereignty of Law, pp. 279–85.

¹²⁶ Allan, “Judicial Deference and Judicial Review”, p. 102. See also Allan, T.R.S., “Deference, Defiance, and Doctrine: Defining the Limits of Judicial Review” (2010) 60 U.T.L.J. 41 CrossRefGoogle Scholar.

¹²⁷ See also Dyzenhaus, “The Politics of Deference”, pp. 294, 298.

¹²⁸ Cf. Hobbes, T., Leviathan ([1651], London 1968), ch 26Google Scholar: “That law can never be against reason, our lawyers are agreed … but the doubt is of whose reason it is that shall be received for law.”

¹²⁹ Mureinik, E., “A Bridge to Where? Introducing the Interim Bill of Rights” (1994) 10 South African Journal of Human Rights 31 CrossRefGoogle Scholar, at 32. See also Dyzenhaus, D., “Law as Justification: Etienne Mureinik's Conception of Legal Culture” (1998) 14 South African Journal of Human Rights 11 CrossRefGoogle Scholar.

¹³⁰ Raz, The Authority of Law, p. 24: “One can be very watchful that it shall not overstep its authority and be sensitive to the presence of non-excluded considerations. But barring these possibilities, one is to follow the authority regardless of one's view of the merits of the case (that is, blindly).”