The general meaning and application of the proportionality principle in EU law has been discussed in Chapter 2.88 Here we will try to provide a somewhat deeper    
understanding of what role proportionality plays in the assessment of the compatibility of national measures with the principle of free movement of goods.
The way in which the Court of Justice deals with proportionality varies considerably between different cases. In some cases proportionality is the subject of a rather extensive analysis, whereas in others the Court confines itself to briefly concluding that a specific national measure is suitable for achieving the stated objective.    
Overall, for a measure to be deemed proportional, the means which it employs must be suitable for the purpose of achieving the desired objective and it should not go beyond what is necessary to achieve that objective.90 It is for the Member State taking the restrictive measure to provide evidence that allows its arguments regarding the measure’s appropriateness and proportionality to be substantiated.91
If the measure is not deemed suitable for achieving the desired objective it is likely to impede the free movement of goods without bringing any environmentally beneficial results which could justify the trade impediment. When the Commission or the Court of Justice questions whether a national measure is in fact suitable for achieving the desired objective, that is tantamount to questioning whether the national measure was in fact prompted by the stated aim—or, to put it more bluntly, whether the Member State is really telling the truth. As to the link between a national measure and a stated justification, the Court has made clear that it is ‘required to examine a justification [based on Article 36 TFEU] only in so far as it is common ground or properly established that the national legislation concerned does in fact pursue the purposes that the defendant Member State attributes to it’.92
Determining whether a national measure is suitable for achieving the desired objective can be quite challenging—not least if the desired effects are long-term or concern small effects on large groups or complex systems. Rather than trying to assess the actual outcome of the measure, the Court of Justice has opted for looking at the manner in which a Member State pursues the objective. It has, for example, found that a measure is ‘appropriate for ensuring attainment of the objective pursued only if it genuinely reflects a concern to attain it in a consistent and systematic manner’.93 It seems thus that a measure must appear to be reasonably well designed and not be inconsistent with other measures relating to similar objectives. However, the Court is unlikely to require perfect consistency between the handling of similar risks by any individual Member State. Considering the complex nature of many environmental problems, such a requirement would be hard to maintain in practice, and would easily be perceived as a very far-reaching restriction on the Member States’ ability to devise their own policies. It is particularly with respect to national measures that have far-reaching repercussions for free movement that the measures would seem easier to justify if they form part of a consistent policy of securing attainment of a public interest objective.94
The issue of whether a measure is more far-reaching than necessary can also be phrased as whether there is any other measure that could achieve the same desired objective with less negative impact on free movement. If so, the measure at issue will normally not be deemed proportional. Requiring that a certain circumstance be proven by means of a specific document is for example likely to be deemed excessive and, therefore, disproportionate if that circumstance can be proven by the presentation of other documents.95
In some cases the Court of Justice has explicitly required that the Member State assesses the existence of alternative means of attaining the same objective. Presumably the obligation to look for alternative measures becomes more demanding the more trade-impeding the contemplated measure is. In a case concerning a ban on lorries carrying certain goods on a section of motorway constituting a vital route of communication between certain Member States, the Court found that
the Austrian authorities were under a duty to examine carefully the possibility of using measures less restrictive of freedom of movement, and discount them only if their inadequacy, in relation to the objective pursued, was clearly established.96
Identifying and accounting for every conceivable alternative measure could easily become a Herculean task, effectively rendering it impossible for the Member States to adopt any measures with more far-reaching impacts on trade between Member States. The Court has recognised this risk by holding that even though each Member State which invokes an imperative requirement as justification for the hindrance to free movement of goods has to demonstrate that its rules are appropriate and necessary, ‘that burden of proof cannot be so extensive as to require the Member State to prove, positively, that no other conceivable measure could enable that objective to be attained under the same conditions’^7
A highly practical issue is obviously how costly or cumbersome an alternative measure can be and still qualify as a reasonable alternative which has to be chosen before a more trade-restrictive measure. Aims of a purely economic nature can generally not justify barriers to the free movement of goods78 It would seem obvious, however, that Member States must be allowed to disregard measures which hypothetically could be used to achieve an environmental objective but which would be excessively costly or complicated to implement. A Member State could otherwise be placed in a position where it was prohibited to take an otherwise appropriate measure because of the existence of alternative measures which it for practical     
reasons could not reasonably avail itself of. In this regard the Court of Justice has established that Member States must be able to attain, for example, an environmental objective ‘by the introduction of general rules which are necessary on account of the particular geographical circumstances of the Member State concerned and easily managed and supervised by the national authorities’."
When determining whether trade-restrictive measures meet the proportionality requirement, the Court of Justice also considers the extent to which the national measures give the operators concerned reasonable time to adapt to the new circumstances.     This may also apply to changes of existing measures. In its assessment of a German deposit-and-return system for certain used packages, the Court held that the legislation at issue
complies with the principle of proportionality only if, while encouraging the reuse of packaging, it gives the producers and distributors concerned a reasonable transitional period to adapt thereto and ensures that, at the time when the packaging-waste management system changes, every producer or distributor concerned can actually participate in an operational system.101
If the national measures are as far-reaching as a general ban, the proportionality requirement may be met by allowing for those operators finding it particularly challenging to find suitable substitutes for the banned product to apply for exemptions. In ToolexAlpha a system of individual exemptions from a general ban on trichloroethylene was considered appropriate and proportionate since it offered increased protection for workers, while at the same time taking account of the undertakings’ need for continuity. Under the applicable law an exemption could only be granted in cases where no safer replacement product was available and provided that the applicant continued to seek alternative solutions which are less harmful to public health and the environment.102
National authorities can also need some time to adjust to new circumstances, for example by ameliorating the trade impeding effects of trade-restrictive measures. In Mickelsson and Roos a general prohibition on the use of personal watercraft on waters other than general navigable waterways had been adopted in Sweden. However, the national regulation at issue provided for the designation on a regional basis of additional waters on which personal watercraft may be used. The fact that no such additional designation had yet been made three weeks after the entry into force of the national regulation did not necessarily make the prohibition non-proportional, since consideration had to be given to the fact that the competent authority may not have had the necessary time to prepare the measures in question.103
When it comes to national measures that require prior inclusion on an ‘authorised list’ for the marketing of certain goods, thus making the marketing of those goods more difficult and more expensive, and consequently hindering trade between the Member States, the Court of Justice has applied a number of criteria that such a measure must meet to be proportional.       The drawing up of such a list and any subsequent amendments to it must be based on objective and nondiscriminatory criteria.105 The legislation at issue must also make provision for a procedure enabling interested parties to have new products or new kinds of goods included in the list. The procedure must be easily accessible and must be capable of being concluded within a reasonable time. Any decision to refuse the inclusion of a new product must be open to challenge before the courts.^6 An application to obtain the inclusion of a product in such a list may be refused only if its authorisation would pose a genuine risk to the protection of or compliance with any of the interests listed in Article 36 TFEU or otherwise recognised as imperative requirements under EU law.107
-  Dir 2009/28/EC (n 84), para 80. The Court also indicates that it applied the same kind of reasoning in Case C-379/98 PreussenElektra (n 78), although without stating that clearly.
-  See, eg, Case C-309/02 Radberger (n 23).
-  87 Opinion of Advocate General Jacobs in Case 379/98 ECLI:EU:C:2000:585, paras 231—33.Advocate General Geelhoed has supported this view and pointed out that it would be inconsistent ifnon-arbitrary discriminatory environmental measures could be maintained or adopted by a MemberState in an area subject to secondary EU law according to Art 114(4) and (5) TFEU (see further section4.3) but would not be susceptible to an exception from Art 34. Opinion ofAdvocate General Geelhoedin Case C-320/03 ECLI:EU:C:2005:459, para 106.
-  See section 2.4.3.
-  See further Jacobs ‘The Role of the European Court’ (n 75) 197.
-  Case C-233/94 Germany v Parliament and Council ECLI:EU:C:1997:231, para 54.
-  On the meaning of ‘substantiate’ and the varied terminology applied by the Court of Justicein this context see N Nic Shuibhne and M Maci ‘Proving Public Interest: The Growing Impact ofEvidence in Free Movement Case Law’ (2013) 4 Common Market Law Review 965—1005, 982.
-  92 Case C-165/08 Commission v Poland ECLI:EU:C:2009:473, para 53.
-  Case C-169/07 Hartlauer Handekgeselkchaf ECLI:EU:C:2009:141, para 55.
-  See further G Mathisen ‘Consistency and Coherence as Conditions for Justification of MemberState Measures Restricting Free Movement’ (2010) 47 Common Market Law Review 1047.
-  Case C-443/10 Bonnarde (n 32), paras 35—38.
-  96 Case C-320/03 Commission vAustria (n 18), para 87.
-  CaseC-110/05 Commission vItaly (n 8), para 66.
-  Case C-120/95 Decker ECLI:EU:C:1998:167, para 39. There seems, however, to be an increasing acceptance of economic arguments in some policy areas. Nic Shuibhne and Maci ‘Proving PublicInterest’ (n 91) 998.
-  Case C-142/05 Mickelsson and Roos (n 68), para 36.
-  1°° Case C-320/03 Commission vAustria (n 18), para 90.
-  Case C-309/02 Radberger (n 23), para 81.
-  ш2 CaseC-473/98 Toolex Alpha ECLI:EU:C:2000:379, paras 46—47.
-  Case C-142/05 Mickelsson and Roos (n 68), para 42.
-  The Court of Justice has dealt with ‘authorised lists’ in a number of cases, relating to different kinds of goods. For example, Case C-219/07 Nationale Raad van Dierenkwekers en LiefhebberstECLI:EU:C:2008:353 concerned a Dutch prohibition on the holding or trading in mammals belonging to species not included in a ‘positive’ list, whereas Case C-192/01 Commission v DenmarkECLI:EU:C:2003:492 concerned a requirement for prior authorisation of foodstuffs to which vitamins and minerals have been added.
-  Case C-219/07 Nationale Raad (n 104), para 34.
-  1°6 Ibid, para 35 and Case C-333/08 Commission vFrance (n 45), para 81.
-  1°7 Case C-219/07 Nationale Raad (n 104), para 36 and Case C-192/01 Commission v Denmark (n104), para 46 with further references.
-  See, eg, Case 174/82 Sandoz ECLI:EU:C:1983:213, para 16 (foodstuffs to which vitamins havebeen added); Case C-443/02 Schreiber ECLI:EU:C:2004:453, para 43 (plant protection products);and Case C-333/08 Commission v France (n 45), para 85 (processing aids and foodstuffs).
-  Case C-333/08 Commission v France (n 45), para 85 with further references.
-  See L Kramer EU Environmental Law (7th edn, Sweet & Maxwell, 2012) 96 and J H Jans andH H B Vedder European Environmental Law (Europa Law Publishing, 2012) 285—8.