The application of the principle of equal liberty to the constitution produces the principle of participation which is assumed to be "equal" though the nature of this equality, as we shall see, is a peculiar one. It defines political rights in the most general sense and is equal in terms of rights to take part in and determine the outcome of the constitutional process that establishes the laws with which citizens are expected to comply. Now, the "original position" specified such an equal status to all parties and the constitutional convention that was discussed at its conclusion further indicated ways in which the "original position" was to be left as continuing to incorporate the principles that governed its construction. But Rawls now adds that the constitution produced within the well-ordered society should be such that it involves a "transfer" of the principle of participation from the "original position" to the constitution. The point of this is that the constitutional process should "preserve the equality of the original position to the degree that this is practicable". The qualifying clause at the close of this statement will, however, turn out to be important.
Section 36 discusses the principle under "favourable conditions" whilst section 37 indicates "adjustments" to existing conditions which implies a split in Rawls' discussion of the principle of participation but this split is not one between "ideal" and "non-ideal" theory. The rationale of the split is rather to first state the elements of constitutions and then to indicate the reasons for the limitations of these elements by other factors arising from the "circumstances of justice". In section 36 the elements of the constitutional regime are made clear including the selection of a legislature in which there is the view that political parties should "advance some conception of the public good" and not be mere interest groups. The conception of the election of this legislature is understood here to be governed by a relation to the electorate in which each member of the latter has an equivalent vote and equal rights to become members of the legislature. Guarantees of liberty are also referred to and it is assumed that a lack of unanimity is part of the "circumstances of justice".
After these preliminaries Rawls goes on to discuss the way that the definition of equal liberty by the principle of participation is to be understood by discussing the meaning of the principle. Its meaning is again specified in terns of each vote having equal weight, something that is related here to equality of constituencies and safeguards against gerrymandering. Also included in the "meaning" of the principle of participation are the earlier points about equality of access to public office with the usual provisos granted concerning age and residence.
After discussing the "meaning" of the principle of participation in these ways Rawls turns next to the "extent" of its sway. The basic sense he gives to the question of "extent" is the degree to which the majoritarian principle holds sway. As this principle is restricted so is the extent of the principle that much more narrow. The extent of the principle is, naturally, narrowed by reference to such constitutional devices as the separation of powers and the adoption of bills of rights which, as adopted, are then not susceptible to political will in the sense that they are constitutional provisos that govern the way in which such will can be manifested. Assuming that these ways of narrowing the extent of the principle apply to all equally they do not violate the fairness of the principle of participation.
After discussing the "meaning" of the principle of participation and its "extent", Rawls turns next to the way that the constitution can ensure that political liberty possesses "worth" for the citizens. Everyone must have the right to use the public forum and a fair chance to add proposals to the political agenda. However there are countervailing pressures that work against such formal guarantees, not least in relation to inequality of means of relating to the political process, as manifested in market societies by wealth (and in other societies by status). In order that these pressures should not remove the "worth" of political liberties there are needed "compensating steps" as Rawls terms them. In a market society political parties could be given public support to free them from the pressures incurred by seeking donations for example.
In Section 37 Rawls turns to limits on the principle of participation although the scope of such limits was already laid out in some degree in section 36. One of the key such limits concerns the "extent" of the principle's sway through the majoritarian principle being curtailed in application. Such limitation of the majoritarian principle is governed by the way in which this guarantees the greater security and extent of other liberties. Included here are freedom of conscience and freedom of the person, two liberties which bare majoritarian rule could over-ride. The point of the constitutional procedure is to find a way of ensuring such liberties are protected without unduly narrowing the principle of participation's extent. What is not allowed scope in narrowing the principle of participation is, however, mere strength of feeling in a minority as this alone makes no specific reference to principles of justice.
After indicating the basis on which limitations of the principle of participations "extent" can be justified Rawls turns next to limitations of its "meaning" in terms of how some "unequal" liberties could in practice be granted in the constitution despite its overall aim being one of maintaining a position akin to that achieved in the "original position". Such a limitation shows that the "equality" attained in the achieved constitution may not be complete although any such limitation of its equality has to be one that can be justified to those placed in a disadvantaged position by it. It would be one that, in fact, enhanced the protection of the other liberties of those so disadvantaged.
The means by which the "meaning" of the principle of participation could be thus restricted is discussed in terms of the conception of universal equal suffrage being open to limitation. This is an historically recent notion and one that was not accepted by John Stuart Mill or Kant. Rawls does not here discuss, as he could have done, Kant's division of the citizenry between "active" and "passive" members or the account of "independence" that underpinned it. Instead Rawls describes Mill's reasons for granting extra votes to persons with "greater intelligence and education" in order that the judgment of the wiser be given more weight. This does not prevent all from possessing the vote but does require differential weighting of votes. In describing this notion Rawls does not condemn Mill's view but nor does he specifically endorse it. It is rather mentioned for the purpose of illustrating the means by which the "meaning" of the principle of participation could be restricted in application.
One of the problems with proposals like Mill's is, however, that it threatens also to restrict the "worth" of political liberties to the disadvantaged and this worth is part of the bond of citizenship. By means of the process of citizenship it is intended, after all, to raise the sight of all to interests broader than their own and this broadening is not purely a means of political liberty but an essential end of them. Whilst Rawls concludes his discussion with this account of "worth" he does not reflect, as one might think he should, on how it would be reduced by the reduction in the "meaning" of the application of the principle of participation.