This brings us to the second pillar of the anti-entrenchment position, which might be called the “quasi-constitutive” argument. Professors McGinnis and Rappaport, who pioneered this argument, explain:
If a legislature could pass a measure that would prevent a successor from taking action, then that measure would function as a constitutional restraint on the future legislature. For example, if the Senate passed a rule prohibiting tax increases, that would function exactly as if it were a constitutional prohibition on tax increases. . . . Because the Constitution permits amendments only under the procedures in Article V and not simply through legislative enactments, the legislature does not have the power to bind itself in the future.
J. McGinnis & M. Rappaport, The Constitutionality of Legislative Supermajority Requirements: A Defense, 105 Yale L. J. 483, 505-06 (1995).
The McGinnis/Rappaport argument can be somewhat hard to understand because, as the title of their article indicates, they defend the authority of a legislative body to adopt rules that prevent a simple majority from exercising legislative power that it would otherwise have under the Constitution. This is acceptable, they maintain, so long as the majority retains the ultimate power to amend or waive the rules.
So, if I understand their argument correctly, it actually would be permissible for the Senate to adopt a rule prohibiting any tax increases, notwithstanding the language quoted above. The constitutional infirmity would exist if the Senate prohibited repeal of this rule (or required a supermajority to repeal it). So long as the majority has the ability to waive or amend the rule, however, McGinnis and Rappaport see no constitutional violation.
Still, it is an open question what this actually means. For example, suppose a measure to raise taxes is introduced in the Senate and a point of order is raised that the measure violates the (hypothetical) Senate rule. According to McGinnis and Rappaport, the point of order could not be overcome by the argument that the rule is unconstitutional. But it seems that supporters of the measure could argue that (1) they are entitled to a vote on whether or not to waive the rule and (2) in the absence of such a vote, the rule is unconstitutionally entrenched. If this is true, it is not clear why McGinnis and Rappaport would so vigorously defend the constitutionality of supermajority rules because it would seem that such rules would be largely meaningless.
Fortunately, McGinnis and Rappaport appear to recognize this problem in their 1995 article. They explicitly distinguish rules that prohibit a majority from changing or waiving an existing rule, on the one hand, and rules that prevent the majority from obtaining a final vote on changing or waiving the rule, on the other. The Senate rule allowing filibusters of proposed rule changes, they make clear, falls into the latter category:
If the Senate voted on whether to change the cloture rule, only a simple majority would be needed to change it. It is true that an attempt to change the cloture rule might be filibustered, but that is another matter. The historical and structural argument presented above does not demonstrate that a majority must at all times be able to obtain a vote on all measures that it desires.
105 Yale L. J. at 507 (emphasis added).