International commitments must be "domesticated" to give them legal force at the domestic level. This process involves a number of steps from ratification to interpretation to implementation to enforcement. Some factors influencing the process of domestication include:
In the U. S. and most other advanced industrial democracies, major environmental agreements require action by the legislature. The Framework Convention on Climate Change (FCCC), for example, generally requires ratification and a formal process of implementation. To come into force internationally, the FCCC requires ratification by 50 nations. This was achieved in March, 1992.
In terms of how they are treated under domestic law, international agreements fall into three main categories. One type is the informal, "housekeeping" accord which does not require ratification; this includes executive agreements. Another type is a ratifiable treaty with direct effect, requiring no transformation into domestic laws. A third type requires both ratification and transformation. Most environmental accords are of this third type, though some can be implemented (transformed) through prior existing legislation.
The primary purpose of ratification is to grant consent. Until ratification occurs and is received, a state is not fully bound by treaty obligations. Ratification also allows a government to review the terms of an accord. It reinforces the principle of consent embodied in national sovereignty. In addition, it provides time for the party countries to enact any necessary changes in domestic laws needed to enforce the treaty domestically. It typically gives legislatures a formal and important role in the process of international cooperation (this role varies with the institutional structure of the political system).
There is significant variation from country to country in ratification and transformation processes. These differences reflect domestic, not international law. For example, in the U. S., "treaties" must be consented to by the Senate, but often, major agreements are handled as executive or congressional-executive agreements. Treaties are the equivalent of domestic law, and can therefore be thwarted by later laws. They cannot violate the Constitution. Executive agreements have an unclear status; they can be overturned more easily than by legislation.
In the United Kingdom, the making of a treaty is an executive act (called "Royal," though not actually undertaken by the Queen), but the carrying out of treaty obligations requires an Act of Parliament. Treaties have the same status as in the U. S.
In France, major treaties need parliamentary approval, and have a higher status than normal domestic law. Under French law, in order to carry domestic obligations, a treaty must be reciprocally in force in the other parties. This is something of moving target; it is not always clear if other countries are reciprocating. France maintains this loophole in all its international agreements.
In the Netherlands, international treaty obligations are superior to both prior and later domestic law. This is novel approach among nations and shows the highest level of deference to international law. With a two-thirds majority vote, treaties can even overturn Constitutional rules. Major treaties are subject to parliamentary approval in the Netherlands.
Though there are clearly significant institutional differences, these differences can sometimes fade away in practice as governments and courts can choose to apply different rules or precedents in different cases. In reconciling international treaties with domestic laws, most countries seek to reconcile the two whenever possible. This is also sometimes selectively applied.
Some countries, such as Italy, take the treaty and lay it directly into a domestic act. Other countries reword it and create new domestic legislation with the rewording. In enforcing such legislation, a court can look at the treaty or the rewording of it. In the U. S., the courts will usually look to the implementing or enabling legislation if there is a conflict between that legislation and the original treaty. Typically, enforcement by the courts is not of the treaty, it is of U. S. laws that implement the treaty.
For example, in the FCCC, some obligations may be able to be enforced domestically under existing U. S. legislation while others measures, such as a proposed carbon tax, would require implementing legislation. No new legislation has been needed for most major recent international environmental treaties. For example, the Montreal Protocol was domestically implemented through the Clean Air Act. Though the U.S. has so far not ratified the Biodiversity Convention, it could do so without any new legislation. On the other hand, the international convention on dumping waste at sea did required new implementing legislation.
The need for ratification and transformation poses obstacles for the effective implementation of international commitments. There are some ways of possibly getting around problems of domestication. It is possible to create annexes which can incorporate change in obligation without ratification. Another possibility, with a negative rule, is to oblige states to actively opt out of altered commitments, rather than opt in. It is also possible to design commitments which can make use of already-existing legislation in important nations. Finally, wholly executive or soft-law (non-binding) agreements can be used.
These methods pose a number of normative and constitutional problems, however. They make use of the fact that foreign relations and policy decisions are concentrated in the executive branch in all cases. The executive has enormous discretion in international affairs under the Act of State doctrine in which normal rules don't apply.
In the cases of the North American Free Trade Agreement and the World Trade Organization, distinctions are blurred between domestic and international authority. New rules are established at the international level that will be binding nationally, but these rules are not passed in the usual democratic manner. In such cases, that level of executive power may be troublesome. Hence there may be a tradeoff between effectiveness in international regimes and democratic principles and procedures.
With the FCCC and other new treaties coming into force in the near future, the situation will get more complicated as such treaties get more in depth in terms of domestic laws. More transparency is needed in how each country undertakes implementation of treaties so the international community can learn from the various processes.