Redistricting is a very important part of the democratic process. Unfortunately, much of the work of redistricting takes place behind closed doors. Legislators and political consultants decide which streets or neighborhoods are in or out, specialists make the maps, and the public has little opportunity to weigh in. Districts are often crafted for political gain--a practice known as gerrymandering.
There is some hope for reform. Good government advocates have become increasingly vocal about gerrymandering. In some states, like California, there is a push to make the redistricting process more transparent and to involve citizens in the redistricting process. At the federal level, The Fairness and Independence in Redistricting Act (H.R. 3025 & S. 1332) would prohibit states from carrying out more than one Congressional redistricting after a decennial census and would require states to conduct redistricting through a public, bipartisan commission.
A district’s compactness (or lack of compactness) is often used as a proxy for gerrymandering. Academics, state legislatures and Supreme Court Justices have all cited compactness, along with contiguity, as a "traditional" districting principle. Unfortunately, the legal standard for compactness has been similar to Justice Stewart’s famous definition of obscenity: I know it when I see it.
Some proponents of redistricting reform, most prominently Daniel D. Polsby and Robert D. Popper, have advocated strongly for the use of quantitative compactness standards as an evaluative tool in the redistricting process. A low quantitative compactness score can serve as a useful indicator that a particular district shape is irregular, and this may point to a gerrymander at work. But a non-compact district might not have been gerrymandered at all. No mathematical technique--such as the generation of a compactness score--is likely to adequately correct for all of the geographical and social variability that can result in irregular district shapes. How compact is your district? Check it out on our district search page.
Of course! Some districts landed at the top of our least-compact districts lists because of physical geography—a shoreline, a mountain range, a river or some other natural feature created convoluted district boundaries rather than back-room political dealings. The state senate district MA-Cape & Island—the district that encompasses Cape Cod—is an excellent example of this.
In urban areas, high population densities mean that districts are often formed by aggregating very small geographical areas, such as census block groups, which typically leads to far more contorted boundaries than the aggregation of large areas, like counties, in more rural areas. Districts may also be drawn to follow other kinds of non-compact administrative boundaries, such as city limits.
Additionally, unusually shaped districts may reflect patterns in human geography. To conform to the Voting Rights Act, district boundaries may be drawn to bring together geographically dispersed racial minority populations so that they may have the opportunity for meaningful electoral representation.
All of these conditions can contribute to the production of districts with a low compactness score for some measures.
*For a discussion of the biases of various compactness measures, see H.P. Young, "Measuring the Compactness of Legislative Districts," Legislative Studies Quarterly, 13 (1), 1988, pp. 105-115.