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                         DECLARATION OF JUDGE AD HOC GUILLAUME

                 [Translation]
                    1. In its Judgment of 16 December 2015, the Court found “that Nica-
                 ragua has the obligation to compensate Costa Rica for material damages
                 caused by Nicaragua’s unlawful activities on Costa Rican territory” (Cer-
                 tain Activities Carried Out by Nicaragua in the Border Area (Costa Rica v.
                 Nicaragua) and Construction of a Road in Costa Rica along the San Juan
                 River (Nicaragua v. Costa Rica), Judgment, I.C.J. Reports 2015 (II),
                 p. 740, para. 229, subpara. (5) (a)). Since the Parties failed to reach an
                 agreement on the amount of compensation due, “the question of
                 compensation . . . will [now] be settled by the Court” (ibid., p. 741,

                 para. 229, subpara. (5) (b)).
                    2. Costa Rica assesses the material damage it has sustained at
                 US$6,711,685.26, while Nicaragua estimates it to be no more than
                 US$188,504. The Court rejected the majority of Costa Rica’s submissions
                 and fixed US$358,740.55 as the principal sum of the compensation due.
                 I supported this assessment, but would like to clarify my views on certain
                 points.
                    3. As noted by the Court, “Costa Rica claims compensation for
                 two categories of damage” (Judgment, para. 36). First, it sought
                 US$2,880,745.82 for “quantifiable environmental damage caused by
                 Nicaragua’s excavation of the first caño in 2010. . . and a further [eastern]
                 caño in 2013” (ibid.). Second, it requested compensation of US$3,828,031.14
                 for various expenses allegedly incurred as a result of Nicaragua’s unlaw-
                 ful activities.
                    4. On the latter point, my comments will be brief. On the former, they
                 will be more detailed.

                                           The Applicable Law
                    5. Early in its Judgment, the Court recalled the relevant principles of
                 the law of international responsibility, noting that “the breach of an
                 engagement involves an obligation to make reparation” (ibid., para. 29).
                 According to the well‑known dictum of the Permanent Court in the Fac-
                 tory at Chorzów case, reparation is intended to “wipe out all the conse-
                 quences of the illegal act and re‑establish the situation which would, in all
                 probability, have existed if that act had not been committed” (Factory at
                 Chorzów, Merits, Judgment No. 13, 1928, P.C.I.J., Series A, No. 17,
                 p. 47). The International Law Commission stated in its Draft Articles on
                 State Responsibility that “[f]ull reparation for the injury caused by the
                 internationally wrongful act shall take the form of restitution, compensa-
                 tion and satisfaction” (Art. 34). Whenever possible, however, restitution
                 in kind should be preferred (Factory at Chorzów, Merits, Judgment

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                 No. 13, 1928, P.C.I.J., Series A, No. 17, p. 47). If this form of reparation
                 “is materially impossible or involves a burden out of all proportion to the
                 benefit deriving from it, reparation takes the form of compensation or
                 satisfaction” (Pulp Mills on the River Uruguay (Argentina v. Uruguay),
                 Judgment, I.C.J. Reports 2010 (I), p. 103, para. 273; see also para-
                 graph 31 of the Judgment).
                    6. In this case, neither Party contemplated restitution, i.e. the rehabili-
                 tation of the sites by Nicaragua. The Court’s task is thus limited to fixing
                 the amount of compensation due to Costa Rica.
                    7. When ruling on a request for compensation,
                      “the Court [considers] whether an injury is established. It . . . then
                      ‘ascertain[s] whether, and to what extent, the injury asserted by the
                      Applicant is the consequence of wrongful conduct by the Respond-
                      ent’, taking into account ‘whether there is a sufficiently direct and
                      certain causal nexus between the wrongful act . . . and the injury suf-
                      fered by the Applicant’ (Application of the Convention on the Preven-
                      tion and Punishment of the Crime of Genocide (Bosnia and
                      Herzegovina v. Serbia and Montenegro), Judgment, I.C.J. Reports
                      2007 (I), pp. 233‑234, para. 462). If the existence of injury and causa-
                      tion is established, the Court . . . then determine[s] the valuation.”
                      (Ahmadou Sadio Diallo (Republic of Guinea v. Democratic Republic
                      of the Congo), Compensation, Judgment, I.C.J. Reports 2012 (I),
                      p. 332, para. 14; see also paragraph 32 of the Judgment.)
                    8. The sole purpose of the compensation due is to make reparation for
                 the injury suffered. It does not depend on the seriousness of the acts alleged.
                 Consequently, and as recalled by the Court, “[c]ompensation should
                 not . . . have a punitive or exemplary character” (Judgment, para. 31).
                    9. “[A]s a general rule”, and in accordance with extensive jurisprudence,
                 “it is for the party which alleges a particular fact in support of its claims to
                 prove the existence of that fact”. However, the Court does not exclude the
                 possibility that, in certain cases, “this general rule . . . [has to] be applied
                 flexibly”, in particular when the respondent “may be in a better position to
                 establish certain facts” (Ahmadou Sadio Diallo (Republic of Guinea v.
                 Democratic Republic of the Congo), Compensation, Judgment, I.C.J. Reports
                 2012 (I), p. 332, para. 15; see also paragraph 33 of the Judgment). This is
                 not the case here, however, since it is in fact Costa Rica alone which has
                 access to the disputed area, that area falling under its sovereignty. Thus,
                 when examining each of the heads of damage alleged by the Applicant, the
                 Court was right to seek to determine whether Costa Rica had established
                 the existence of the damage, the causal link between the damage and Nica-
                 ragua’s unlawful activities and the cost of that damage.
                    10. Having set out these principles, it is necessary to examine
                 Costa Rica’s submissions regarding the material damage sustained. I will
                 divide these submissions into three categories:
                 (a) expenses which have been or will be incurred with a view to reducing
                     environmental damage through appropriate work;

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                 (b) compensation due for damage which will remain in spite of such
                     work;
                 (c) certain ancillary expenses incurred between 2010 and 2015, inter alia,
                     to visit, overfly and acquire satellite images of the sites.

                                        Site Restoration Expenses

                   11. Let us first examine the expenses which may have been or may be
                 incurred by Costa Rica to rehabilitate the sites.
                   12. Here, Costa Rica seeks reimbursement of US$195,671.02 for
                 expenses incurred in constructing a dyke across the 2013 eastern caño to
                 prevent it from connecting the San Juan River to the sea. Nicaragua
                 assesses the reimbursable expenses under this head at US$153,517. The
                 Court awarded US$185,414.56 (Judgment, para. 146). Although I find
                 this assessment generous, I cannot object to it.

                    13. Second, Costa Rica seeks US$54,925.69 for replacing the soil
                 removed from the caños. The Court was right to reject this claim (ibid.,
                 para. 87). The caños have in fact largely refilled and revegetated naturally.
                 It is therefore hard to see why almost 10,000 cubic metres of earth should
                 now be emptied into them, at the risk of destroying the vegetation that
                 has already regrown there. Moreover, the Secretariat of the Ramsar Con-
                 vention did not recommend such restoration.

                    14. This leaves Costa Rica’s claim for compensation in the amount of
                 US$2,708.39 for the “restoration of the wetland”. This would clearly be
                 welcome, and Costa Rica’s claim is thus justified in principle. I would
                 note, however, that the Applicant provides no details of the work it
                 intends to carry out to that end or of the timescale for that work. Although
                 I share the majority opinion of the Court on this point (ibid.) I would
                 like to express here my hope that this work will actually be planned and
                 carried out.

                          Compensation for Lasting Environmental Damage

                    15. Compensation for the construction of the dyke and for the restora-
                 tion of the wetland could not make full reparation for the environmental
                 damage caused to Costa Rican territory. Costa Rica assesses the lasting
                 damage resulting from the excavation of the first caño in 2010 at
                 US$2,148,820.82, and the lasting damage resulting from the excavation of
                 the 2013 eastern caño, at US$674,290.92, namely US$2,823,111.74 in
                 total. It claims nothing in respect of the western caño excavated in 2013.
                    Using a different method of assessment, Nicaragua estimates this dam-
                 age at no more than US$34,987. Nicaragua’s experts add, however, that

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                 if Costa Rica’s method of assessment were to be applied, and the errors
                 corrected, the amount of compensation due would increase to US$84,296.

                    The Court awarded US$120,000 to Costa Rica under this head (Judg-
                 ment, para. 86).
                    16. Before I examine the Parties’ arguments in detail, it is important to
                 recall that the first caño excavated in 2010 was intended to connect the
                 San Juan River to Harbor Head Lagoon. It was just over 1 km long and
                 no more than 15 m wide, and two-thirds of it was excavated on grazing
                 land. However, the works undertaken by Nicaragua did lead to the felling
                 of trees of various sizes across an area of some two and a half hectares in
                 total.
                    The eastern caño excavated in 2013 — far shorter than the first — was
                 intended to connect the San Juan River to the sea, but the excavation
                 work was stopped before the connection could be made; as we have seen,
                 a dyke was then built to avoid any risk of the river connecting with the
                 ocean.
                    Finally, the San Juan River is known to carry large amounts of sedi-
                 ment, which have led to a considerable extension of its delta. In the
                 absence of any clearing activities, that sediment has accumulated in the
                 caños, which have become obstructed by natural means. The satellite
                 images show that the two areas are now completely revegetated.
                    These circumstances should be borne in mind when examining the Par-
                 ties’ submissions.
                    17. Costa Rica contends that Nicaragua’s unlawful activities have
                 caused the following ecosystem goods and services to be lost:
                 (a) standing timber;
                 (b) other raw materials;
                 (c) gas regulation;
                 (d) natural hazards mitigation;
                 (e) soil formation and erosion control; and
                 (f) biodiversity, in terms of habitat and nursery.
                   18. Costa Rica evaluates the loss connected with these various goods
                 and services by referring to values obtained for other locations in the
                 existing documentation and applying these values to this case. It thus
                 adopts what is generally known as a “benefits transfer” approach. How-
                 ever, it uses a different method to assess the loss of standing timber, rely-
                 ing on the local market price.

                   19. Nicaragua does not deny that these various types of damage are
                 compensable, but states that some of them do not exist and that the
                 method adopted by Costa Rica to assess others is flawed. It adds that the
                 Applicant has made some serious errors in the application of its own
                 method of assessment.
                   For its part, Nicaragua proposes evaluating the damage sustained by
                 determining the overall “replacement costs”, i.e. the “price that would

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                 have to be paid to preserve an equivalent area until the services provided
                 by the impacted area have recovered”.
                    20. International law does not impose the use of any particular method
                 for evaluating damage. It should be noted, however, that the
                 United Nations Compensation Commission, founded in the aftermath of
                 Iraq’s invasion of Kuwait, adopted the approach favoured by Nicaragua.
                 It may also be noted that this same approach was adopted in United
                 States legislation, in the Oil Pollution Act, and in the European Union’s
                 Environmental Liability Directive. That said, it is for the Court to deter-
                 mine the amount of compensation due by conducting the most accurate
                 assessment possible, leaving aside quibbles over methodology.

                    21. A careful examination of the Parties’ calculations leads me to
                 believe that, in fact, each of these approaches carries serious risks of
                 error.
                    22. I will begin with Costa Rica’s calculations. The first head of alleged
                 damage concerns the trees felled during the excavation of the caños.
                 Costa Rica estimates that 50 per cent of this timber could have been sold
                 immediately, and uses the market rate to calculate its value. It then asserts
                 that half of the trees’ annual growth could also have been utilized. The
                 sum of these two values is US$19,558.64 for the 2010 caño and
                 US$1,970.35 for the 2013 eastern caño, amounting to US$21,528.99 for
                 the first year. Believing that it will take at least 50 years for the trees to
                 recover naturally, and applying a discount rate of 4 per cent, Costa Rica
                 ultimately seeks US$462,490 in compensation under this head.

                     23. This calculation raises three problems of varying importance:
                 (a) First, it should be noted that this assessment is not intended to deter-
                     mine the environmental damage caused by the trees’ disappearance
                     (on account of their possible role in the absorption of carbon, for
                     example). The only thing at issue here, as Costa Rica itself has
                     observed, is the damage resulting from the disappearance of “timber”
                     belonging to it. One might be surprised to see Costa Rica seeking
                     reparation for such damage, when the trees in question were part of
                     a protected wetland in which any kind of forest exploitation is pro-
                     hibited. Even in the absence of action on Nicaragua’s part, this timber
                     would never have been sold and Costa Rica would not have profited
                     from it. Consequently, the clearing carried out by Nicaragua did not
                     deprive Costa Rica of any income‑generating capital. Costa Rica’s
                     claim on this point thus raises a serious problem. The Court acknowl-
                     edged this in refusing to use this method of calculation (Judgment,
                     paras. 76 and 78‑79).
                 (b) Second, in my view, Costa Rica makes a mistake in basing its calcu-
                     lation on the notion that the trees could have been cut and sold each
                     year for 50 years. In reality, once they have been cut and sold, the
                     trees take some time to regrow. They cannot be re‑cut and re‑sold

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                     every year for 49 years. The damage resulting from the timber’s dis-
                     appearance is not incurred on an annual basis.

                     Furthermore, Costa Rica does little to contest this in its Reply on the
                     question of compensation, and merely states that, in terms of national
                     accounting, the value of the felled trees will be lost from the nation’s
                     assets for 50 years (subject to its gradual recovery). The Court was
                     rightly unconvinced by this reasoning. After they have been felled,
                     the trees cease to be part of the nation’s assets. Once paid, the com-
                     pensation will in turn form part of the assets and the accounts will be
                     in order.
                 (c) In addition to these fundamental observations, I would point out that
                     certain other aspects of the Applicant’s calculations are open to
                     challenge.
                     Costa Rica’s count includes a number of trees measuring over 10 cm
                     in diameter. It estimates the average age of these trees to be 115 years
                     for the 2010 caño. This calculation is questionable: there can be no
                     doubt that the age of the trees in this caño has been unduly inflated,
                     since Costa Rica’s experts failed to take account of the youngest spec-
                     imens when calculating the trees’ average age. Moreover, it seems to
                     me that those experts believed themselves able to identify trees older
                     than the very soil in which they were said to have grown. The trees
                     in the 2013 eastern caño were clearly younger. On these bases,
                     Costa Rica fixes the recovery period for the forest at 50 years. Nica-
                     ragua’s experts accept a period of 20 to 30 years. The truth is probably
                     somewhere between the two.
                     Furthermore, account must be taken of the fact that this recovery will
                     be gradual. Costa Rica claims in its Reply on the question of com-
                     pensation that the 4 per cent discount rate takes this into considera-
                     tion. But that is not correct: the discount rate should aim to take
                     account of the fact that, instead of receiving compensation each year
                     throughout the entire recovery period, Costa Rica will receive a single
                     payment in 2018 corresponding to the current value of those annual
                     instalments.
                     After correcting some of these errors by Costa Rica, Nicaragua’s
                     experts, applying the Applicant’s own method, conclude that the
                     amount of compensation due here should be no more than US$30,175.
                     This figure is a little low, but it gives an approximate idea of the
                     damage sustained under this head.
                    24. Continuing my examination of the heads of damage claimed by
                 Costa Rica, I now turn to the other raw materials (fibre and energy) that
                 were lost. Costa Rica evaluates the damage resulting from the loss of
                 these raw materials at US$832.20 for the first year. It then bases its calcu-
                 lation on the assumption that it will take 50 years for the raw materials to
                 recover, applies a discount rate of 4 per cent and, ultimately, requests
                 compensation in the amount of US$17,877.

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                    I have serious doubts about the evaluation of this damage. We have
                 seen no proof that the vegetation cut back to the ground by Nicaragua
                 was used locally for its fibres (to make baskets, for example) or as fuel, or
                 that it could be used to provide such services. Moreover, the alleged
                 damage is assessed using the benefits transfer approach, on the basis of
                 unclear criteria. The 50‑year period is particularly unjustified, since the
                 vegetation in question recovers over a far shorter period than is needed
                 for tree regrowth, as recognized by the Court (Judgment, paras. 76
                 and 82).
                    That vegetation nonetheless helped maintain the ecosystem in that wet-
                 land which is protected under the Ramsar Convention. Compensation is
                 due on this account.
                    25. A more difficult question is that of gas regulation and air quality.
                 Costa Rica assesses the corresponding damage over one year at
                 US$43,641.24. Then, allowing for a recovery period of 50 years and
                 applying a discount rate of 4 per cent, it requests compensation in the
                 amount of US$937,509.
                    Costa Rica is probably entitled to compensation on this account, but
                 its calculation contains a number of errors:
                 (a) That calculation is made using the benefits transfer approach using a
                     base value of almost US$15,000 per hectare, a value taken from the
                     thesis of a Costa Rican student, who adopts a figure considerably
                     higher than those usually applied.
                 (b) Costa Rica uses this figure for both the eastern caño excavated in 2013
                     and the one excavated in 2010, even though it is undisputed that the
                     vegetation in these areas was very different.
                 (c) More serious still, by applying the figure for the first year to the entire
                     50‑year‑recovery period, its assessment is incorrect. A distinction
                     must be made between:
                      — the site’s existing carbon stock, which was diminished by the
                         destruction of the vegetation (which should be counted only
                         once); and
                      — the reduction in the site’s annual carbon sequestration in the
                         future.
                   Account must also be taken of the fact that, as the trees and vegetation
                 recover, greater quantities of carbon will gradually be sequestered. This
                 phenomenon could even occur quite quickly, since young, growing trees
                 sequester more carbon than those which have reached maturity.

                   Nicaragua’s experts re‑calculated the amount of compensation due
                 using the method advocated by Costa Rica, applying the per‑hectare
                 value put forward by the Applicant, and correcting only the errors made.
                 The figure they arrived at was US$47,778, which is much more realistic in
                 my view.
                   26. Finally, it is not in dispute that the caños’ excavation has harmed

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                 the biodiversity of the wetland protected under the Ramsar Convention.
                 Compensation is due on this account. However, it is difficult to assess this
                 harm, because Costa Rica provides only scant information about the situ-
                 ation before 2010 and 2013, about the impact of the work undertaken by
                 Nicaragua and about the planned restoration measures (see paragraph 14
                 above).
                    27. I will not dwell on the last two heads of damage invoked by
                 Costa Rica: in my view, this damage has not been established and there is
                 thus no need for any calculations to be made.
                 (a) The Court found that Costa Rica had failed to demonstrate that the
                     work carried out by Nicaragua had impaired the ability of the area
                     in question to mitigate natural hazards such as earthquakes or flood-
                     ing (Judgment, para. 74). I agree with this finding. Moreover, and
                     assuming that such hazards did emerge following the excavation of
                     the caños, the measures taken and the natural development of the area
                     have caused them to disappear. There is, in particular, no longer any
                     risk of coastal erosion or salt‑water intrusion in the river due to the
                     construction of a dyke across the 2013 eastern caño, a fact which
                     appears to be corroborated by the Report of the Ramsar Advisory
                     Mission No. 77 of August 2014.
                 (b) As noted by the Court (ibid.), the same is true for soil formation
                     and erosion control. Moreover, Costa Rica does not dispute that the
                     caños are being refilled naturally. It simply claims that there is a dif-
                     ference between the soil carried by the river and the soil which was
                     removed. However, Costa Rica has failed to prove that this difference,
                     assuming it to be established, is having noticeable effects on the
                     environment.
                    In short, if one uses Costa Rica’s method of assessment, after the nec-
                 essary corrections have been made to it, a figure in the order of US$85,000
                 is reached, as noted by the Court (ibid., para. 84).

                   28. I find the method used by Nicaragua to be more satisfactory in
                 principle, although it is not easy to determine the replacement cost in this
                 instance. Nicaragua does so by referring to Costa Rica’s forest protection
                 scheme, under which compensation of US$309 per hectare is paid each
                 year to forest owners who agree to take protective or preventive measures
                 to enable their forests to continue providing environmental services to
                 society and to safeguard them for future generations. Applying this figure
                 to the 6.19 hectares damaged over a period of 30 years and using a dis-
                 count rate of 4 per cent, Nicaragua’s experts estimate the replacement
                 cost to be no more than US$34,987. This approach is no better than the
                 one employed by Costa Rica. Indeed, like the Court (Judgment, para. 77),
                 I doubt that the sums paid by Costa Rica to encourage landowners to
                 protect their forests correspond exactly to the damage suffered by the
                 environment in the protected wetland.

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                    29. In sum, I find it difficult to reach a completely accurate evaluation
                 of the damage in this instance. In such a situation, the amount of dam-
                 ages should not be determined by mere speculation or guess. Evidence of
                 the extent of the damage must be shown; however, it may be shown as a
                 matter of just and reasonable inference, even though the result would be
                 only approximate (see paragraph 35 of the Judgment). In the present cir-
                 cumstances, the Court was right to retain some elements of Costa Rica’s
                 assessment, as corrected by Nicaragua (Judgment, para. 86), and to
                 award compensation of US$120,000, a figure which, given the uncertain-
                 ties inherent in assessing this type of damage, I was able to support.

                      The Ancillary Expenses Incurred between 2010 and 2015

                    30. In addition, Costa Rica seeks US$80,926.45 in compensation for
                 expenses incurred between October 2010 and March 2011 while attempt-
                 ing to verify the nature and scope of Nicaragua’s unlawful activities on
                 the disputed territory (overflights, first UNITAR/UNOSAT report, sal
                 aries, satellite images). The Court found that the amount of compensa-
                 tion payable under this head was US$21,647.20 (ibid., para. 106). In my
                 view, this assessment is justified.
                    31. Lastly, Costa Rica seeks compensation of US$3,551,433.67 for
                 expenses incurred for monitoring the disputed territory between
                 March 2011 and December 2015. The Court only awarded Costa Rica
                 compensation in the amount of US$28,970.40 for overflights, the pur-
                 chase of satellite images and the second UNITAR/UNOSAT report (ibid.,
                 para. 131).
                    32. I agree with this assessment. In my view, the Court was right, in
                 particular, to refuse to reimburse Costa Rica for various police expenses
                 incurred by it. Costa Rica claimed to have established two police posts
                 close to the disputed territory in order to carry out its obligations under
                 the Order on the indication of provisional measures of 8 March 2011
                 (Certain Activities Carried Out by Nicaragua in the Border Area
                 (Costa Rica v. Nicaragua), Provisional Measures, Order of 8 March 2011,
                 I.C.J. Reports 2011 (I), p. 6). However, the first police post at Laguna de
                 Agua Dulce had already been set up in December 2010. Furthermore, the
                 Outgoing Report of Costa Rica’s Minister of Public Security, covering
                 the period between May 2010 and April 2011, states that Costa Rica has
                 launched a programme to protect both its northern and southern land
                 boundaries, involving the re‑establishment of a border police force at
                 45 outposts.

                   The establishment of the police posts was therefore part of a policy by
                 Costa Rica to defend its territory in a general way. They were not set up
                 to respond to the concerns expressed by the Court in paragraph 78 of its
                 Order of 8 March 2011, encouraging the Parties to co‑operate in order to

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                 prevent the development of criminal activity in the disputed territory
                 (I.C.J. Reports 2011 (I), p. 25).

                    Thus, Costa Rica fails to establish that the creation of the police posts
                 was a clear and direct consequence of the unlawful activities of which
                 Nicaragua is accused. As the Court found (Judgment, para. 127), these
                 expenses are not compensable.
                    33. In any event, the corresponding personnel expenses could not be
                 compensated, since salaries would have been paid to those concerned
                 even if Nicaragua had not acted. In fact, it is clear from statements made
                 by Costa Rica’s then Minister of Public Security, Mr. Mario Zamora
                 Cordero, that the police deployed at Isla Portillos were simply officers
                 who had been reassigned. The special border police unit was formed,
                 according to the same minister, “by taking human and financial resources
                 from other operational structures of the police”. Costa Rica does not
                 claim to have paid special allowances or overtime to the officers in ques-
                 tion. Those officers simply received their regular salaries. Their reassign-
                 ment did not generate any additional expenses for Costa Rica. In
                 accordance with the jurisprudence of the United Nations Compensation
                 Committee, founded in the aftermath of Iraq’s invasion of Kuwait —
                 jurisprudence which I believe should be upheld — no compensation is
                 payable to Costa Rica under this head.

                   34. The same conclusions must be reached, for the same reasons, with
                 regard to the equipping of the biological station and the remuneration of
                 the officers assigned to that station, such as the salaries of the Costa Rican
                 coast guards and pilots.

                                           Pre‑judgment Interest

                    35. With this case, the Court has, for the first time, awarded pre‑
                 judgment interest to the Applicant, taking the opportunity to explain
                 that “pre‑judgment interest may be awarded if full reparation for injury
                 caused by an internationally wrongful act so requires” (Judgment,
                 para. 151). In this instance, the Court refused to grant such interest on
                 the amount awarded in compensation for the damage caused to the envi-
                 ronment, that sum already making full reparation for that damage. It did
                 however award pre‑judgment interest on the expenses incurred by
                 Costa Rica with a view, inter alia, to preventing further harm. In my
                 view, this is a sensible solution, which is justified by the specific circum-
                 stances of the case and leaves room in the future for assessments to vary
                 from case to case.

                 (Signed) Gilbert Guillaume.

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