Abstract This article and its sequel examine an argument that has become a shibboleth for the European pro-attitude towards international and supranational legal arrangements. I call it the argument from transnational effects. The argument says that supranational or transnational forms of integration, in particular market integration, are desirable on account of democracy itself. National democracies find themselves thereby forced to confront and to internalise the externalities that they cause for one another. A fortiori, democracy becomes supposedly emancipated from the confines of the nation state. Since the argument favours normative limitations on national political processes it seems to lend strong support to the introduction of transnational constitutional discipline. In this article and its sequel it is claimed that the argument, correctly understood, cannot support the creation of transnational democracy. Rather, in a critically recalibrated form, the argument, paradoxically, provides strong backing for the existence of bounded political communities without, for that reason, succumbing to ontologically questionable beliefs about the essence of national communities. Hence, the argument is really as much about the limits set to transnational integration as it is about their legitimacy. This explains why it is of central relevance to constitutionalism in a global age. The opening sections of this article offer an interpretation of John Hart Ely's constitutional theory. Examining the latter helps to articulate adequately the democratic sensibility expressed in the argument. It is argued that Ely's theory exceeds the scope of a mere theory of judicial review. It presents, indeed, a theory of constitutional authority, which is highly relevant to an analysis of the argument from transnational effects. The article then distinguishes and discusses two different readings of the representation-reinforcing task that Ely attributes to constitutional legality. According to one reading, representation is secondary and only ancillary to the realisation of equality. According to another reading, equal participation is prerequisite to the success of representative democracy whose aim is to discover common ground. It is concluded that the first reading is easier to accommodate in a transnational setting. It will be seen that Ely's theory—at any rate, the first reading of it—is basically concerned with the problem addressed by the argument from transnational effects. This article's discussion of the argument distinguishes two different types of situation. A third, more general type will be dealt with in a subsequent article. The first situation affects people who realise that they would be better off if they were to benefit from the laws of a different democracy. Hence, they would like to have these laws imported. It is argued that their interests do not find support in the argument from transnational effects. The second situation concerns someone who encounters obstacles when moving from one democracy to another. Such obstacles can emerge either as a result of discrimination against non-nationals or from the sheer fact that laws between and among bounded societies are different. The antidote against the latter is to submit national legislation to a proportionality test. Even though reinforcing representation prima facie seems to support this conclusion, the article claims that virtual representation, correctly understood, actually restricts the sweep of constitutional control to cases of behavioural discrimination. Extending the scope of control would actually violate the respect that it is owed to national democratic autonomy pursuant to the principle of virtual representation. It is also shown that only by limiting its sweep the argument from transnational effects can be prevented from endorsing neoliberal political goals.