Geof Stone, "Understanding Cause and Effect"
How do we know when to abandon a successful policy? At first blush, this might seem a contradiction in terms. Why would one ever abandon a successful policy? But most policies have costs as well as benefits, and at a certain point one might decide that the ongoing costs outweigh the ongoing benefits, even though that might not have been true earlier. Making such judgments requires a clear-eyed understanding of cause and effect.
Four current issues illustrate the problem. Consider, first, the recent five-to-four decision of the Supreme Court in Shelby County v. Holder to hold section 5 of the Voting Rights Act of 1965 unconstitutional. Writing the majority opinion, Chief Justice John Roberts reasoned that the requirement that certain jurisdictions with a long history of racial discrimination in voting must get pre-approval from the Justice Department before changing their voting laws is no longer constitutional because, whatever might have been the case in 1965, the record shows that the percentage of African-Americans who vote in those jurisdictions is now more or less on par with the percentage of White-Americans who vote. Thus, in Roberts' words, "the conditions that originally justified section 5 no longer characterize voting in the covered jurisdictions," section 5 is therefore no longer necessary, and, accordingly, it is now unconstitutional.
The illogic in this reasoning is so self-evident that it is difficult t