قوانین مسئولیت تحت انتشار بازرگانی بین المللی GHG

Article 17 of the Kyoto Protocol authorizes emissions trading, but the rules governing emissions trading have been deferred to subsequent conferences. In designing and implementing an international greenhouse gas (GHG) emissions trading scheme, assigning liability rules has been considered to be one of the most challenging issues. In general, a seller-beware liability works well in a strong enforcement environment. In the Kyoto Protocol, however, it may not always work. By contrast, a buyer-beware liability could be an effective deterrent to non-compliance, but the costs of imposing it are expected to be very high. To strike a middle ground, we suggest a combination of preventive measures with strong but feasible end-of-period punishments to ensure compliance with the Kyoto emissions commitments. Such measures aim to maximize efficiency gains from emissions trading and at the same time, to minimize over-selling risks.

Emissions trading under Article 17 of the Kyoto Protocol would promote buyers’ compliance with their emission limitation and reduction commitments by reducing their costs of compliance. Because selling parts of assigned amounts is likely to prove highly profitable, trading would also provide an economic incentive for Parties to sell their assigned amount units (AAUs) that are ultimately needed at the end of the commitment period for their own compliance purposes and would thus create the possibility that a Party could find itself in a situation of non-compliance as a result of its own excessive over-selling. Over-selling could occur unintentionally, wilfully or inadvertently (Nordhaus et al., 2000). Although the exceptions to compliance rules could be made for unintentional over-selling that could occur if emissions increased late in the commitment period as a result of unpredictable events or events beyond the control of the government concerned, no exceptions should be allowed for both wilful over-selling and inadvertent over-selling.1 The question then arises of which Party — the buyer, the seller or both — is liable for non-compliance by the seller who either inadvertently or wilfully over-sells its permits and then fails to comply with its commitment. This problem of over-selling is one of the most challenging issues in designing a workable international emissions trading scheme. Given the fact that Article 12 of the Kyoto Protocol (UNFCCC, 1997) authorizes Annex I countries to acquire the certified credits obtained from the Clean Development Mechanism (CDM) projects with non-Annex I countries,2 the issue of liability for the validity of the credits is of less concern in the CDM case when the credits have been certified.3 Thus, some Party4 suggests that the transfers of AAUs in an international emissions trading scheme could be envisioned along this line. Each year, any excess AAUs to be sold first have to be verified and certified prior to trading. Although the so-called post-verification trading model eliminates the risk of over-selling, there is no guarantee that the Parties who comply until the end of the fourth year of the commitment period will be in compliance with their commitments at the end of the commitment period because they could sell more than their remaining AAUs available in the last, namely, fifth year of the commitment period. Other Party5 even suggests that in order to ensure that Parties only sell those assigned amounts surplus to their compliance requirements, any excess AAUs are allowed to be sold only after compliance has been established. This would increase the environmental performance of the scheme by reducing uncertainty surrounding the validity of acquired permits. In the mean time, however, it would restrict legitimate trading activities during the commitment period. This could significantly increase the costs of participating in emissions trading and thus reduce the volume of trades. Moreover, it still does not eliminate the risk of over-selling, since the surplus assigned amounts from the first commitment period might be needed by the seller during the subsequent commitment periods. Thus, rules that address the risk more effectively and allow trading during the first commitment period need to be established. They are essential to the success of emissions trading (Environmental Defense Fund, 1998). By providing some new insights, this article aims to contribute to the in-depth discussion on the liability rules that are intended to define clearly where the responsibility lies for a Party in case it is out of compliance because of over-selling its AAUs, thus contributing to the design and implementation of an international GHG emissions trading scheme. It should be pointed out that a Party could be in non-compliance with its commitments, whether or not it trades. Non-compliance could also occur because a Party fails to undertake sufficient domestic abatement policies and measures or to purchase enough AAUs or certified credits from the Kyoto mechanisms. Here we focus on the risk of over-selling just because it arises from emissions trading. It is by no means that over-selling deserves greater punishment than other reasons for non-compliance. Indeed, from the atmosphere's perspective, no matter how a Party is out of compliance, the damages to the atmosphere are the same. This suggests that all the reasons for non-compliance should be treated equally.