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Mr. Vsevolod Mazurenko

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Unreasonable and/or Arbitrary Measures in Fair and Equitable Treatment

I. Origin and relationship with fair and equitable treatment


A prohibition on the taking of measures that are arbitrary or unreasonable is commonly included in the non-impairment standard (see Protection against arbitrary and discriminatory measures), and appears in more than 60% of investment protection treaties.1 This standard is most often drafted either as a separate clause,2 or together with the fair and equitable treatment (FET) standard.3 The issue of the relationship between non-impairment and FET standards is not straightforward and case law lacks consistency.4 See also Discrimination in FET.


In the absence of an express clause that sets out a non-impairment standard, actions that are arbitrary or unreasonable could nonetheless be caught by the FET standard5 and minimum standard of treatment.6


Some tribunals held that a fair and equitable treatment would entail a treatment which is reasonable.7 As such, “the standard of ‘reasonableness’ has no different meaning than the ‘fair and equitable treatment’ standard ‘with which it associate’”.8

II. Assessment of arbitrary/unreasonable measures 


A “measure” is understood to be any act, step or proceeding attributable to the State.9


The terms “unreasonable” and “arbitrary” are not defined in investment treaties. Due to their open-ended nature, they do not lend themselves to a clear-cut definition. Tribunals referred to dictionary definitions in respect to those terms.10


Tribunals assess whether a measure is arbitrary or unreasonable based on substantive and procedural factors. Substantive factors relate to the measures’ rationality and proportionality,11 while procedural factors overlap with denial of justice, lack of due process or lack of due diligence.12


In any case, the assessment of the unreasonable character of a measure for the purpose of an FET breach requires to “consider all the facts and circumstances of an individual case”.13

A. The ELSI test


In Elsi the term “arbitrary” was defined as wilful disregard of due process, an act that shocks or surprises a sense of judicial propriety.14 This approach has been adopted by many tribunals who preferred to decide on a case by case basis instead of laying down definitive criteria.15                                                           


However, it has been criticized by scholars for its excessive flexibility and limited precedent value.16

B. The measure's effect and rational


Another approach considers the measure’s effect and rationale. A governmental measure will be considered 'arbitrary' if there is no relationship between the measure adopted and a legitimate governmental policy. The measure will be considered 'unreasonable' if a justification or a rationale has in fact been provided, but there is no reasonable (or rational) relationship between the purported justification and a legitimate governmental policy.17


Tribunals assess the measure’s effect or rationale based on its merits. It is not enough for the respondent to justify an action by relying on a source of authority, but, rather, it must “also overcome the Claimant’s contention that the authority was exercised in an unreasonable and arbitrary fashion”.18


In one case, the tribunal found it to be a reasonable policy for a State “to try to ensure the adaptation of long term contracts to new conditions prevailing in a liberalised economy operating under EU law”.19 

C. The EDF test


A more elaborate test for what counts as an arbitrary measure was adopted in EDF (Services) which is as follows: 

  1. a measure that inflicts damages on the investor without serving any apparent legitimate purpose; 
  2. a measure that is not based on legal standards but on discretion, prejudice or personal preference, 
  3. a measure taken for reasons that are different from those put forward by the decision maker, or 
  4. a measure taken in wilful disregard of due process and proper procedure.20

This test has been endorsed in subsequent case law.21

III. Threshold to characterize a breach


All those approaches require more than mere illegality but something akin to manifest disregard of law22 or even bad faith,23 (although tribunals regularly noted that bad faith is not required to find a breach of the FET standard, (see Fair and Equitable Treatment, Section IV), rising “to the level which is unacceptable from the international perspective”.24


Arbitrariness and unreasonableness triggering violation of the FET standard may be reached by an aggregate of events.25


Dumberry P., The Fair and Equitable Treatment Standard: A Guide to NAFTA Case Law on Article 1105, Kluwer Law International, 2013, pp. 127-274.

Heiskanen, V., Arbitrary and unreasonable measures, in Reinisch A. (ed.), Standards of Investment Protection, Oxford University Press, 2008, pp. 87-110. 

Levashova, Y., The Right of States to Regulate in International Investment Law: The Search for Balance Between Public Interest and Fair and Equitable Treatment, International Arbitration Law Library, Vol. 50, Kluwer Law International, 2019, pp. 173-276.

Lowe, V., Arbitrary and Discriminatory Treatment, in Kinnear, M., Fischer, G.R. et al (eds.), Building International Investment Law: The First 50 Years of ICSID, Kluwer Law International, 2015, pp. 307-318.

Newcombe, A. and Paradell, L., Law and Practice of Investment Treaties: Standards of Treatment, Kluwer Law International, 2009, pp. 233-298.

Rajput, A., Protection of Foreign Investment in India and Investment Treaty Arbitration, Kluwer Law International, 2017, pp. 87-126.

Reisman, W. M., Crawford, J.R. et al. (eds.), Foreign Investment Disputes: Cases, Materials and Commentary, 2nd ed., Kluwer Law International 2014, pp. 583-752.

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