1. The tort is known by many names, such as unlawful interference with trade, intentional interference with business by unlawful means, unlawful interference with business, intentional infliction of harm by unlawful means, causing loss by unlawful means, etc. I have chosen to use unlawful interference with economic relations since this seems to capture best the current scope and use of the tort.

2. Besides the privity anomaly mentioned herein, another of the tort's anomalies is that it seems to provide an uncharacteristically strong protection of the plaintiff's purely economic interests, especially when compared with the protection (or lack thereof) provided to such interests in negligence.

3. See Carty, H An Analysis of the Economic Torts (Oxford University Press, 2001) p 103.Google Scholar

4. Carty, H The need for clarity in the economic torts’ (2005) 16 King's College LJ Google Scholar 165 at 170.

5. Palsgraf v Long Island R Co 248 NY 339 (1928) at 343–344 per Cardozo J. For a similar statement, see Letang v Cooper [1965] 1 QB 232 (CA) at 246–247 per Diplock LJ: ‘[The] distinction between a duty which is “particular” because it is owed to a particular plaintiff and a duty which is “general” because the duty owed to the plaintiff is similar to that owed to everyone else is fallacious in relation to civil actions. A has a cause of action against B for any infringement by B of a right of A which is recognised by law. Ubi jus, ibi remedium. B has a corresponding duty owed to A not to infringe any right of A which is recognised by law. A has no cause of action against B for an infringement by B of a right of C which is recognised by law. B has no duty owed to A not to infringe a right of C, although he has a duty owed to C not to do so’. See also Bourhill v Young [1943] AC 92 (HL) where similar sentiments were expressed by the court.

6. Stevens, R Torts and Rights (Oxford University Press, 2007) p 173 CrossRefGoogle Scholar, citing Leigh and Sillavan Ltd v Aliakmon Shipping Co Ltd, The Aliakmon[1986] 1 AC 785 (HL); Hunter v Canary Wharf Ltd[1997] AC 655 (HL); Best v Samuel Fox & Co Ltd[1952] AC 716 (HL); Kapfunde v Abbey National plc[1999] ICR 1 (CA). For a similar view, see at p 184: ‘Each part of private law has – and must have – its own suitably specified idea of privity’.

7. Zipursky, BC Rights, wrongs, and recourse in the law of torts’ (1998) 51 Vanderbilt L Rev 1 Google Scholar at 3.

8. Witness the fate of the ‘anomalous’ tort of simple conspiracy which has ‘attracted more controversy among academic writers than success in practical application’: Lonrho Ltd v Shell Petroleum Co Ltd (No 2)[1982] AC 173 (HL) at 188 per Lord Diplock. See also Gronow, M Conspiracy: the tort that failed?' (1995) 3 Torts LJ 255 Google Scholar at 255: ‘Hardly any of the reported modern attempts to bring an action for…conspiracy have been successful’.

9. [2007] UKHL 21, [2007] 4 All ER 545.

10. See, eg, the master's tort doctrine as developed in Twine v Bean's Express Ltd[1946] 1 All ER 202 (CA) and Broom v Morgan[1953] 1 QB 597 (CA) and the theory presented in Weinrib, EJ The Idea of Private Law (Cambridge University Press, 1995 Google Scholar) at 185–187.

11. See Bazley v Curry[1999] 2 SCR 534 which (unconvincingly) posits that the need for compensation and deterrence provide the necessary justification for the exception. For a discussion and criticism of the various rationales, see Neyers, JW A theory of vicarious liability’ (2005) 43 Alberta L Rev 287.Google Scholar

12. For one effort, see Sales, P and Stilitz, D Intentional infliction of harm by unlawful means’ (1999) 115 LQR 411 Google Scholar, discussed below.

13. Carty, above n 3, pp 103–104.

14. For a refutation, see Neyers, above n 11, at 292–296.

15. See Smith, SA Contract Theory (Oxford University Press, 2004) p 36 Google Scholar on the appropriateness of these criteria for interpretative theories of law.

16. As used in this paper, coherence means more than non-contradiction. It also demands that the internal components of a theory ‘exemplify a single theme’ and constitute a unitary whole, rather than merely being ‘an aggregate of conceptually disjunct or inconsistent elements that…happen to be juxtaposed’. See Weinrib, EJ ‘Legal formalism: on the immanent rationality of the law' (1988) 97 Yale LJ 949 CrossRefGoogle Scholar at 968–969.

17. As to the history of the tort and its relation to the other economic torts such as inducing breach of contract (both direct and indirect), intimidation, conspiracy (both simple and unlawful means) and malicious falsehood, see Carty, above n 3, for a thorough analysis. In OBG, the House of Lords essentially accepted Carty's thesis that the torts (1) of inducing breach of contract directly and (2) of unlawful interference with economic relations are not reducible to one another since inducing breach of contract (directly) is a manifestation of secondary or accessory liability for another's breach of contract, whereas the unlawful interference tort is a manifestation of primary liability. Thus, if unlawful interference with economic relations is a genus tort, it is a genus of only those torts which require unlawful means (such as inducing a breach of contract (indirectly), intimidation and unlawful means conspiracy). For an in-depth discussion of these issues post-OBG and an examination of which of these two principles explains which of the classic cases, see Carty, H Obg Ltd v Allan: the House of Lords shapes the economic torts and explores commercial confidences and image rights’ (2007) 15 Torts LJ 283 Google Scholar; ) at ss 29.8 ff and s 29.86.

18. Oliphant, above n 17, at s 29.85.

19. See Murphy, J Street on Torts (Oxford University Press, 12th edn, 2007) p 378 Google Scholar; accord Carty ‘OBG Ltd v Allan’, above n 17.

20. Its existence was first suggested by several of their Lordships in Allen v Flood [1898] AC 1 (HL); see, eg, Lord Watson at 102–103; Lord James at 180; Lord Davey at 173–174.

21. See the similar, albeit four-part, formulation given in Murphy, above n 19, p 378 and Associated British Ports v TGWU [1989] 1 WLR 939 (CA) at 953. See also OBG, above n 9, at [47] per Lord Hoffmann: ‘The essence of the tort therefore appears to be (a) a wrongful interference with the actions of a third party in which the claimant has an economic interest and (b) an intention thereby to cause loss to the claimant’. For a succinct statement of these elements in three parts, one which relies on and is consistent with English law, see Reach MD Inc v Pharmaceutical Maufacturers Association of Canada (2003) 227 DLR (4th) 458 (Ont CA).

22. OBG, above n 9, at [148] per Lord Nicholls of Birkenhead: ‘In English law it is now well established that “unlawful means” is an essential ingredient of this tort. This goes back to the decision in Allen v Flood’. To similar effect, see the summary of English law by Lord Dunedin in Sorrell v Smith [1925] AC 700 (HL) at 718–719: ‘In the first place, every one has the right to conduct his own business upon his own lines, and as suits him best, even although the result may be that he interferes with other people's business in so doing.…Secondly, an act that is legal in itself will not be made illegal because the motive of the act may be bad…Thirdly, even although the dominating motive in a certain course of action may be the furtherance of your own business or your own interests, as you conceive those interests to lie, you are not entitled to interfere with another man's method of gaining his living by illegal means…’. For a historical and theoretical discussion, see Oliphant, above n 17, at ss 29.2–29.6.

23. On the debate, see Murphy, above n 19, p 379; and Stevens, above n 6, p 189.

24. OBG, above n 9, at [62].

25. Lord Hoffmann's judgment is ambiguous on this point, whereas the dissenting judgment of Lord Nicholls seems to accept this as intentional: see [167] where his Lordship states that intention includes situations ‘where a defendant seeks to advance his own business by pursuing a course of conduct which he knows will, in the very nature of things, necessarily be injurious to the claimant’. For a discussion of this issue, see Carty ‘OBG Ltd v Allan’, above n 17, at 291–292; Oliphant, above n 17, at s 29.89.

26. Torquay Hotel Co Ltd v Cousins [1969] 1 All ER 522 (CA) at 530. For a detailed discussion of the cases, see Carty, above n 3, pp 109–117.

27. Compare Carty, above n 3, who supports the narrower interpretation, with Sales and Stiltz, above n 12, who support the broader view.

28. See OBG, above n 9, at [49]–[51] per Lord Hoffmann: ‘In my opinion, and subject to one qualification, acts against a third party count as unlawful means only if they are actionable by that third party. The qualification is that they will also be unlawful means if the only reason why they are not actionable is because the third party has suffered no loss…Unlawful means…does not in my opinion include acts which may be unlawful against a third party but which do not affect his freedom to deal with the claimant’. As Carty points out, this formulation of unlawful means cleverly ‘includes the tort of intimidation within the unlawful interference tort’; see Carty ‘OBG Ltd v Allan,’ above n 17 at 292.

29. OBG, above n 9 at [152–162].

30. Which in the end concurred with that of Lord Hoffmann.

31. Ibid at [269]. Accord: Carty ‘OBG Ltd v Allan’, above n 17, at 294 (‘it is hard not to agree with Lord Walker's prediction’).

32. 11 East 574n.

33. [1903] 2 KB 600 (CA).

34. [1913] AC 781 (PC) at 793.

35. See, eg, Ex P Island Records [1978] 1 Ch 122 (CA) at 136 where his Lordship states: ‘[a] man who is carrying on a lawful trade or calling has a right to be protected from any unlawful interference with it’.

36. Allen v Flood, above n 20. See especially the discussions of Lord Herschell (at 138–139); Lord Shand (at 166–167); Lord Davey (at 172–174).

37. Quinn v Leathem [1901] AC 495 (HL) at 534. See also the judgment of Lord Brampton (at 525–526) where he stresses the right to trade as being the key to understanding the liability imposed.

38. See Hohfeld, WN Some fundamental legal conceptions as applied in judicial reasoning’ (1913) 23 Yale LJ 16 CrossRefGoogle Scholar at 36–37 where he argues in relation to Lord Lindley's opinion: ‘A “liberty” considered as a legal relation (or “right” in the loose and generic sense of that term) must mean, if it have any definite content at all, precisely the same thing as privilege, and certainly that is the fair connotation of the term as used the first three times in the passage quoted. It is equally clear, as already indicated, that such a privilege or liberty to deal with others at will might very conceivably exist without any peculiar concomitant rights against “third parties” as regards certain kinds of interference…The only correlative logically implied by the privileges or liberties in question are the “no-rights” of “third parties.” It would therefore be a non sequitur to conclude from the mere existence of such liberties that “third parties” are under a duty not to interfere, etc. Yet in the middle of the above passage from Lord Lindley's opinion there is a sudden and question-begging shift in the use of terms. First, the “liberty” in question is transmuted into a “right,” and then, possibly under the seductive influence of the latter word, it is assumed that the “correlative” must be “the general duty of every one not to prevent,” etc’.

39. As Atkin LJ explained in Ware and de Freville Ltd v Motor Trade Association [1921] 3 KB 40 (CA) at 79: ‘the right of the individual to carry on his trade or profession or execute his own activities, whatever they may be, without interruption, so long as he refrains from tort or crime, affords an unsatisfactory basis for determining what is actionable, in as much as the right is conditioned by a precisely similar right in the rest of his fellow men. Such co-existing rights do in a world of competition necessarily impinge upon one another…’.

40. Lazarev, Nikolai Hohfeld's analysis of rights: an essential approach to a conceptual and practical understanding of the nature of rights’ (2005) 12 Murdoch University Electronic Journal of Law Google Scholar, available at E-Law: https://elaw.murdoch.edu.au at 11.

41. As Diplock LJ noted in Letang v Cooper, above n 5, at 246–247: ‘The fact that in the earlier cases the emphasis tends to be upon the duty merely reflects changing fashions in approach to juristic as to other social problems, and must not be allowed to disguise the fact that right and duty are but two sides of a single medal’.

42. Sales and Stilitz, above n 12.

43. It was also at one time supported by Tony Weir; see Weir, JA Chaos or cosmos? Rookes, Stratford and the economic torts 1964 CLJ 225 CrossRefGoogle Scholar at 231.

44. Quinn v Leathem, above n 37, at 534–535.

45. Ibid, at 537.

46. Sales and Stilitz, above n 12, at 412. A similar justification for the tort is offered in Elias, P and Ewing, K Economic torts and labour law: old principles and new liabilities 1982 CLJ 321 CrossRefGoogle Scholar at 338 where they argue that the combination of an intention to harm and an unlawful act ‘creates a sufficient nexus between plaintiff and defendant for the creation of legal liability’.

47. [1895] AC 587 (HL). See also Rogers v Dutt (1860) 15 ER 78 (PC) at 90: ‘an act to be a tort must prejudicially affect the plaintiff in some legal right; merely that it will do him harm in his interests is not enough’.

48. See Tate & Lyle Industries Ltd v Greater London Council[1983] AC 509 (HL) and the discussion in Weinrib, E The passing of Palsgraf?’ (2001) 54 Vanderbilt L Rev 803 Google Scholar at 805.

49. Re Polemis and Furness, Withy and Co [1921] 3 KB 560 (CA).

50. Overseas Tankship (UK) Ltd v Morts Dock and Engineering Co Ltd [1961] 1 All ER 404 (PC).

51. Sales and Stilitz, above n 12, at 418.

52. ‘If…a fundamental element…is D's intention to harm P, the problem of identifying which wrongful means qualify as unlawful means for the purposes of the tort becomes less acute’: ibid, at 414.

53. See ibid, at 418 fn 13, where they argue that ‘the merit of a focus on unlawful means, rather than some wider, more nebulous concept of improper means, is that it provides a clear guide…’.

54. Anns v Merton LBC [1978] AC 728 (HL).

55. See the definition of coherence offered in n 16.

56. See Seavey, W Mr Justice Cardozo and the law of torts’ (1939) Columbia L Rev 20 CrossRefGoogle Scholar at 34 where he lays out this notion of coherence. For a coherent limitation of liability, see Caparo Industries plc v Dickman[1990] 2 AC 605 (HL) where the court limited the liability of the defendant auditors for the same reasons that liability would be imposed (in that case, the scope of the assumption of responsibility).

57. Sales and Stilitz, above n 12, at 412.

58. I would like to thank Ernest Weinrib and Arthur Ripstein for alerting me to this possibility. For the sake of clarity, it should be noted that the Kantian view of rights is wider than that developed by Hohfeld and thus the doctrine described in this section would include, in Hohfeldian terms, abuses of liberties, privileges, etc, as well as abuse of claim rights. For a discussion see Lazarev, above n 40, at 12.

59. Weinrib, EJ Two conceptions of remedies’ in Rickett, C (ed) Justifying Remedies in the Law of Obigations (Cambridge University Press, 2008 Google Scholar) [forthcoming].

60. Ibid, at text surrounding nn 70–71, relying on Kant, I, The Metaphysics of Morals (Cambridge University Press, 1996) pp 44–45 CrossRefGoogle Scholar. As Weinrib elaborates further: ‘As juridical manifestations of self-determining freedom, rights provide the space within which all right holders may pursue ends of their own. Such ends are consistent with the self-determining freedom of others only if the point of pursuing them is independent of the adverse effect on someone else. When all act to pursue ends of their own in this sense, they all rank equally as persons whose activities can coexist within the system of rights. Conversely, if the freedom to perform an act merely to frustrate the purposes of another were legitimate, rights would be transformed from markers of mutual freedom to instruments of subordination. Accordingly, it would be inconsistent of what is normatively presupposed in the system of rights to allow a right to operate in a way that would harm another without promoting (in the language of the civilians) a “serious and legitimate interest” of the right holder.’

61. As John Finnis notes: ‘This tort of conspiracy to injure has recently been much described as “anomalous”…but on a larger view it is the wide doctrine of the irrelevance of intention (motive), ie of Bradford Corporation v Pickles and Allen v Flood, which is anomalous in the face not only of American and civil law but even of aspects of English common law including not only the tort of conspiracy to injure but also malicious prosecution and the type of nuisance instantiated in Christie v Davey[1893] 1 Ch 316 and Hollywood Silver Fox Farm Ltd v Emmett[1936] 2 KB 468’. See Finnis, J ‘Intention in tort law’ in Owen, DG (ed) Philosophical Foundations of Tort Law (Oxford University Press, 1995) p 229 Google Scholar at p 241 fn 51.

62. Recall Lord Dunedin's summary in Sorrell v Smith, above n 22, at 718–719. See also the judgment of Scrutton LJ in Ware and de Freville, above n 39, at 67 where he states; ‘I take Allen v Flood and Bradford Corporation v Pickles to decide that an act otherwise lawful, though harmful, does not become actionable by being done maliciously in the sense of with a bad motive or with intent to injure another’.

63. See, eg, Finnis, above n 61; Gutteridge, HC Abuse of rights 1933 CLJ 22 CrossRefGoogle Scholar at 22; RVF Heuston and ;

64. Which is the standard for simple conspiracy; see Crofter Hand Woven Harris Tweed Co Ltd v Veitch [1942] AC 435 (HL).

65. Lonrho plc v Fayed [1990] 2 QB 479 (CA) at 488–489.

66. Sorrell v Smith, above n 22, at 719.

67. Weinrib, above n 59, at text surrounding n 69.

68. As occurred in Daishowa Inc v Friends of the Lubicon (1996) 27 OR (3d) 215 (Div Ct) where the defendant was held to have an intention to harm the company even though its motivation for its activities was to aid an aboriginal band in its timber rights dispute with the company.

69. Rookes v Barnard [1964] AC 1129 (HL) at 1215–1216 per Lord Devlin. For a judicial application of ‘Quinn v Leathem without the conspiracy’ see the famous American case of Tuttle v Buck 119 NW 946 (Minn 1909) where a rich banker was held liable for spitefully driving a barber out of business by opening a rival barber shop.

70. See Lonrho (No 2), above n 8, and OBG, above n 9, at [145] where Lord Nicholls forcefully states that ‘Tuttle v Buck…is not the law in England’. See also Sorrell v Smith, above n 22, at 719 where Lord Dunedin calls this view ‘the leading heresy’.

71. As to this doctrine, see Vandevelde, KJ The modern prima facie tort doctrine’ (19901991) 79 Ky LJ 519 Google Scholar and the classic decisions of Holmes J in Aikens v Wisconsin 195 US 194 (1904) and Vegelahn v Gunter 167 Mass 92 (SC Mass 1896). The modern version of the prima facie tort can be found in the Restatement (Second) of Torts (1979) s 870.

72. To my knowledge, this paper is the first time that this theory has been offered as a potential justification.

73. See, eg, Heuston, Rvf Judicial prosopography’ (1986) 102 LQR 90 Google Scholar at 111: ‘The Chief Baron…enjoyed then a great reputation as a jurist. Indeed in 1892 he had been made an English Privy Counsellor – an unprecedented honour for an Irish judge…’.

74. Leathem v Craig [1899] 2 Ir R 667 (Div Ct) at 708.

75. Philco Products Ltd v Thermionics Ltd [1940] 4 DLR 1 (SCC).

76. See Springhead Spinning Co v Riley (1868) LR 6 Eq 551 and the authority collected in Boyce v Paddington Borough Council[1903] 1 Ch 109. Given this history, it is strange to find Lord Wilberforce state in Gouriet v UPW[1978] 1 AC 435 (HL) at 477 that ‘it can said to be a fundamental principle of English law that…public rights can only be asserted by the Attorney-General as representing the public’. This is especially strange in light of the court's acceptance of both Springhead Spinning and Boyce in that very same case. For a more far-reaching argument against Lord Wilberforce's ‘fundamental principle’, see Wade, Hwr ‘The Attorney General and the trade union’ (1978) 94 LQR 4.Google Scholar

77. For a compelling rights-based argument as to why this is so, see Stevens, above n 6, pp 186–187.

78. For an excellent discussion of special damage, see Kodilinye, G Public nuisance and particular damage in the modern law’ (1986) 6 LS 181.Google Scholar

79. For a similar argument, see Sorrell v Smith, above n 22, at 725–726 per Lord Dunedin; Crofter, above n 64, at 443–444 per Viscount Simons.

80. Lonrho (No 2), above n 8, at 186.

81. See Evans, A Breach of statutory duty and unlawfulness in the economic torts’ (1982) 33 N Ir Legal Q 370 Google Scholar at 372–373 where he argues: ‘Certain features of the House's reasoning deserve further consideration.…For instance, it was denied that the orders were imposed for the benefit or protection of a particular class of individuals who were engaged in supplying crude oil or petroleum products to Southern Rhodesia. But it could plausibly be argued that the object of the orders was not simply the destruction, by economic pressure, of the illegal UDI régime but also the restoration, as soon as possible, of lawful status to Southern Rhodesia, carrying with it the resumption of, inter alia, trading links with the United Kingdom for the benefit of those who, like Lonrho, wished to pursue trade between the two countries’.

82. See Spencer, JR Public nuisance: a critical examination 1989 CLJ 55 CrossRefGoogle Scholar at 83 where he argues: ‘The courts may be wrong in refusing to accept the idea that damages should be generally recoverable for losses caused by breaches of the criminal law, but as long as they do so, giving the plaintiff damages for any type of loss merely because the defendant has caused it by committing the crime of public nuisance is anomalous’.

83. Refer to discussions and authority in nn 16 and 56.

84. Oliphant, above n 17, at s 29.93. Moreover, as Oliphant notes (at s 29.92), the original examples of unlawful means given by their Lordships in Allen v Flood were all crimes.

85. [1908] 1 Ch 335 (CA).

86. [1990] 2 QB 479 (CA).

87. Fraud Act 2006, c. 35.

88. [1964] AC 1129 (HL).

89. [1965] AC 269 (HL).

90. [1984] 1 WLR 427 (HL).

91. [1983] 2 AC 570 (HL).

92. See Wedderburn, KW Intimidation and the right to strike’ (1964) 27 MLR 257 CrossRefGoogle Scholar and for powerful arguments against this extension. See also Sorrell v Smith, above n 22, at 730 where it was strongly intimated by Lord Dunedin that only torts were to be considered unlawful means.

93. See Hamson, CJ A note on Rookes v Barnard 1961 CLJ 189 CrossRefGoogle Scholar at 193.

94. See, eg, Stratford v Lindley, above n 89 and Dimbleby v NUJ, above n 90. See also, Hadmor Productions Ltd v Hamilton [1982] 2 WLR 322 (HL).

95. See, eg, Lord Hoffmann's comments in OBG in relation to Merkur and Dimbleby v NUJ, at [43]. See also the judgment of Lord Walker where he states at [264]: ‘The decision of this House in Merkur…should not be followed, so far as it holds that inducing an actual breach of contract is not a necessary ingredient of the Lumley v Gye tort…On these points Lord Nicholls and Lord Hoffmann are at one, and I respectfully concur in their reasoning and conclusions’.

96. Query whether a breach of contract is ever a crime in England. For example, in Canada, a breach of contract is criminal in the circumstances outlined in Criminal Code, RSC 1985, c C-46, s 422(1). The offence reads: ‘Every one who wilfully breaks a contract, knowing or having reasonable cause to believe that the probable consequences of doing so, whether alone or in combination with others, will be…to expose valuable property, real or personal, to destruction or serious injury, [or] to deprive the inhabitants of a city or place, or part thereof, wholly or to a great extent, of their supply of light, power, gas or water…is guilty of an indictable offence…or an offence punishable on summary conviction’. Thus, in Canada the decision in Rookes v Barnard might be justifiable since the breach might have also been a crime.

97. (1853) 2 E & B 216.

98. See Oliphant, above n 17, at s 29.26 (relying on the judgments of Lords Pearce and Donovan in Stratford v Lindley).

99. Stevens, above n 6, p 188. To be fair, Stevens also posits that the tort may be justified since there are no possible policy reasons to negate such liability. As he argues: ‘Once it is established that the defendant's actions are wrongful as against someone, the policy problems of whether the action should be permitted as legitimate competition or reasonable trade union activity or for some other reason fall away and do not have to be addressed. As the court is not being asked to give the answer to questions it lacks the competence to give, there is no objection to the loss being actionable’. ibid, pp 188–189.

100. White v Jones [1995] 2 AC 207 (HL) at 260.

101. Eekelaar, J The conspiracy tangle’ (1990) 106 LQR 223 Google Scholar at 226.

102. Benson, above n 6, p 170. In the end, Benson argues that the only justification for the decision in White v Jones is that the beneficiaries are given standing to enforce the testator's contractual right against the solicitor (a right that would lead to substantial damages) since otherwise this right would be defeated by the deceased estate's inability or unwillingness to sue as the testator would have wanted. Framed in this way, the exception cannot justify an exception being made for the tort of unlawful interference with economic relations since the third party can decide for themselves whether or not to enforce her rights.

103. 1 Peake NPC 270.

104. Arden, M Economic torts in the twenty-first century’ (2006) 40 Law Teacher 1 CrossRefGoogle Scholar at 20.