Mapping Massachusetts

04/01/2011 05:05 pm ET | Updated Jun 01, 2011

Massachusetts, the site of the original gerrymander, remains one of the country's more gerrymandered states. Under the Congressional map in place over the past decade, odd districts abound. The Second, in south-central Massachusetts, has been compared to the Loch Ness Monster. The Fourth, whose core is gritty Bristol County, extends a finger to grab the tony Boston suburbs of Brookline and Newton. Boston itself is split between two districts, one stretching all the way to Cape Cod, even though it has very close to the ideal population for a single district.

Under this plan, Democrats have won every election in every district over the last ten years. (In the 1990s, in contrast, Republicans captured up to two seats.) Democrats retained all ten of their seats in 2010 despite the national Republican wave. Massachusetts is, by a substantial margin, the largest state in the country with a unanimous Congressional delegation.

Since we are now in the middle of redistricting season, I recently drafted a new Massachusetts map for the next decade (during which the state will have nine districts). My effort was part of the project led by Columbia Law School professor Nate Persily. The project aims to create a repository of nonpartisan Congressional district maps for every state in the country. These maps will be available as a reference for the line-drawers themselves, for litigants, for the media, and for the general public.

The map that I drew achieved perfect population equality. Every district either had the ideal population (727,514) or was just one voter off. More importantly, and unlike the state's current map, my plan paid heed to the distinct regions and communities that make up Massachusetts. I placed the city of Boston in a single district. I removed the finger that formerly stretched from Bristol County into Boston's inner suburbs. The Loch Ness Monster is no more. Specifically, the identities of the nine districts that I drew are as follows:

District 1: Western Massachusetts (Berkshire, Hampshire, and Hampden Counties)
District 2: Central Massachusetts (Worcester and Franklin Counties)
District 3: Outer Boston suburbs (mostly Middlesex County)
District 4: Northwest Boston suburbs (mostly Middlesex County)
District 5: North Shore (Essex County)
District 6: Southwest Boston suburbs (mostly Norfolk County)
District 7: Southern Massachusetts (Bristol County)
District 8: South Shore and Cape Cod (Barnstable, Dukes, Nantucket, and Plymouth Counties)
District 9: Boston (Suffolk County)

These districts are also substantially more compact than the current ones, scoring about 50 percent higher on two common compactness tests. One district (District 9) continues to be a minority-influence district, with a combined minority population of greater than 40 percent. And I made non-trivial divisions of only three counties (compared to nine in the current plan), though minor county splits were necessary in four more cases to achieve perfect population equality.

Of course, my plan may have certain political drawbacks. If Boston is kept in a single district, for example, it becomes impossible to use its heavily Democratic voters to shore up other nearby districts. Similarly, if the current Tenth District is reshaped to include more of Plymouth County and fewer of Boston's immediate suburbs, it may turn into a bona fide swing district (a development its representative would not welcome). I also drafted my plan without taking into account the locations of incumbents' homes; as a result, some of them may have been (unintentionally) drawn out of their districts.

These consequences, though, are not necessarily undesirable. The point of redistricting is not to create the best possible map for a particular party or a specific set of incumbents. It is to ensure fair and effective representation for all of a state's voters. So it is a feature, not a bug, that my plan's districts are more equal in population, more compact, and more respectful of geographic communities--but also more unpredictable in their political implications.