I am going to write an insurance contract with you.  We agree that if an accident happens I will cover you unless you a type prone to accident or you don’t try hard enough to avoid an accident.

There are two ways we can implement these conditionals.  We could investigate whether they hold at the time we sign the contract or we could wait until an accident happens.  Since an accident is unlikely to happen, the second method often avoids unnecessary costs of investigation and makes it cheaper to enforce the contract.  That means I can offer you a lower premium.

All of this assumes that the conditions that would nullify the contract are

  1. completely described either in the contract or in law,
  2. fully understood by the insured, and
  3. within the information set of the insured

Arguments against rescision can be based on any one of these three being violated.  Certainly #1 is violated in practice if insurance companies are free to present any evidence suggestive of, for example, pre-existing conditions.  Violations of #2 plagues all economic analysis of contracts, no doubt it is a problem here as well.  And an argument against recision could be based on #3, even if we assume that contracts are complete and voluntary.

Indeed I believe that #3 is the basis for a response to the obvious “If allowing for recision is against the interests of the insured, why don’t insurers compete by offering no-rescision contracts.”  These would have higher premiums for the reasons given above.  Insurees would tend to reject these in favor of lower-premium rescision-permitting contracts when they are not aware of buried, jargon-laden, medical records that would nullify their coverage.  In fact, the asymmetric access to this information superimposes an artificial asymmetric information problem on an insurance market that is already plagued by adverse selection.

Here’s a research problem:  what does a competitive equilibrium look like in an insurance market where both types of contract can be offered?  Assume that the insurer has superior information about documentation of pre-existing conditions, and conditions contract terms on its private information.