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Known Knowns and Known Unknowns in Constitutional Design | Mark Tushnet

Some enduring questions about constitutional design center on constitution writers’ decision either to resolve issues that have surfaced in the drafting process or to defer their resolution to a later stage.[1] In this brief observation I use examples drawn largely from the U.S. experience, but constitution drafters everywhere, including India, have had to confront the issues I address. Donald Rumsfeld’s categories are helpful here. There are known unknowns. These are problems with two characteristics: The drafters know that they will arise, and they have no settled views on how they should be solved. Take the Bankruptcy Clause of the U.S. Constitution. The framers knew that it might be a good idea for the nation to have a bankruptcy law, but they knew that they did not know what a good bankruptcy law would look like – except that it should be the same everywhere in the nation. So, they deferred the design of bankruptcy law to ordinary politics, subject only to a constitutional requirement of uniformity.

Most constitutional provisions empowering legislatures deal with known unknowns. And, in nations whose governments have plenary power, the constitutions authorize legislatures to deal with unknown unknowns once they come into view. Known knowns fall into two categories. The constitution’s drafters know that they face specific issues, such as how to design a lower legislative house, what its relation to an upper house will be, and many more. They also know that people at the time of drafting have views, sometimes strong ones, about how those issues should be resolved. And, finally, they want the constitution they are writing to be adopted. The first category of known knowns are issues that the drafters can – or must – resolve through politics when they are writing the constitution. If the framers of the U.S. Constitution could not decide whether the Senate would have representation based on population or based on equality among the states, the entire enterprise would have collapsed. So, they worked hard to come up with some solution that was politically acceptable.

But, what if the constitution writers come across an issue that they simply cannot resolve politically? Perhaps they can get away with deferring the issue to the future. These problems comprise the second category of known knowns–issues that the writers know are important but cannot resolve. What happens with this second group of known knowns? If everything goes well, the political environment may shift, and a solution that was unavailable at the time of drafting becomes available through ordinary politics. In the United States, perhaps issues related to slavery fell into this group from 1791 to some time between 1820 and 1850.

Things can go wrong, though. Perhaps the writers could not resolve the problem because divisions were both intense and reasonably close. If adopting the constitution requires super-majority support and ordinary legislation (of course) does not, it might turn out that an ordinary majority would enact legislation on the issue that would seem like a betrayal to the minority. Or, perhaps it turns out to be impossible even later on to get majority support for ordinary legislation dealing with the issue.[2] A somewhat stylized version of issues associated with the Afghanistan constitution suggests this issue. There the constitution writers deferred decisions about defining the scope of the supreme court’s jurisdiction because they were unsure about the likely quality and fairness of the judges who would staff the court. As things turned out, once the court was up and running, suspicion persisted, and it turned out to be impossible to get agreement on whether the court should have the power merely to interpret the constitution or also have the power to hold legislation unconstitutional.

The more consequential the deferred issues are, the more serious the problems of governance will be. If drafters put off defining how members of some important body like an electoral commission or an anti-corruption agency are to be selected because doing so is too politically contentious, and the nation faces early elections or serious problems of corruption from the outset, the nation is to have a lot of problems. Even more, once a constitution is adopted, people might not know whether the deferred issue is a known unknown – expected to be amenable to solution through ordinary politics – or a known known in the second category, stuck in because something had to be done if the constitution was to be adopted when the politics surrounding the drafting meant that people could not agree on what should be done. And that too is a prescription for serious political problems.

There is probably nothing analytically interesting to say about what happens when you have important issues in the second category of known knowns. Those involved in implementing such a constitution are likely either to stumble through, adopting one after another basically unsatisfactory solutions, or to give up on the constitution altogether – perhaps a good idea, but probably a bad one. Still, scholars might find the distinctions among known unknowns and the two types of known knowns useful.[3]

Originally published in the Indian Journal of Constitutional & Administrative Law.



[1] Rosalind Dixon and Tom Ginsburg have an important recent article on this question, Deciding Not to Decide: Deferral in Constitutional Design, 9 I-CON 636 (2011), though their focus on what they call “by law” clauses blurs their more important points about why deferral occurs.

[2] The problem would be exacerbated were the constitution writers to specify that the deferred issue was to be resolved by an “organic” law, which typically requires a special majority for enactment.

[3] Dixon and Ginsburg use the language of decision and error costs to address some of the questions I raise. Because the problems are, in my view, basically political, I find that language not particularly illuminating.


Mark Tushnet is William Nelson Cromwell Professor of Law at Harvard Law School.

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