Expectations of a Mapmaker


With the failure of the General Assembly and Governor to approve a map by the court deadline, it now falls to Nathaniel Persily to draw Pennsylvania’s next congressional map. This court-appointed special master is known for his skills as a mapmaker in other states. No matter how skilled, no one is perfect. How will we know if he gets it right in Pennsylvania?

Population Deviation

The court directive to keep counties and municipalities whole was clear. Strong constitutional language bans any splits that are not necessary. Federal courts provide states with some flexibility to district population so they may protect the boundaries of their local governments.

In some instances, by creating districts which vary slightly in population, counties and municipalities may stay whole which would otherwise be split. Pennsylvania law does not require mathematical equality. Federal law allows small deviations to avoid splits.

What does this mean? A split is not “absolutely necessary” when by using a small population variance the result would respect more local government boundaries than is possible by using no variance.

The population deviation they use will be a measure of the Supreme Court’s commitment to apply to congressional districts the constitutional requirement of avoiding splits. If there is a strong constitutional commitment, expect to see a slight population deviation (certainly less than 20 persons overall). If the court direction will not be strictly followed, then expect to see districts of exact mathematical equality.

The Measure of Splits

There are two ways to to count splits:

  1. By Local Government — meaning the number of places which contain at least one split. If Philadelphia is divided into 3 districts, it counts as 1 split by this method.
  2. By “Total Splits” — calculated by taking the number of splits within each local government minus the number of local governments split. If Philadelphia is divided into 3 districts, it counts as 2 splits under this method (3 splits within the city minus 1 city = 2 “Total Splits”).

Will the Court focus only on reducing the number of local governments containing splits? Or will they include the balancing consideration of reducing the number of total splits?

The Philadelphia Test

Adhering to the Court standard of respecting county and municipal boundaries means that Philadelphia would have two congressional districts entirely within the city limits. The remaining population would be assigned to one or two neighboring districts.

Historically, political motivations have kept only one district solely within Philadelphia. In particular, CD-1 has been stretched across Philadelphia and along the southern part of Delaware County. The continuation of this odd configuration would clearly not be the product of following the traditional redistricting principles in the court order.

Will the Court permit political considerations to intrude on their map? Or will they be willing to disrupt political deals in order to achieve constitutional compliance?

The Southwest Special

A Special Election is underway in the southwest corner of the state. But the current district boundaries show no respect for county and municipal boundaries. In correcting the violation to neutral redistricting principles, will incumbent and candidate residences be given any consideration both here and across the state?

Oddly shaped district boundaries often indicate an outside motivating force creating an artificial district boundary. Beware of any unusual district formations. They are a warning flag of a possible constitutional issue. Sometimes a closer examination will reveal a sound reason for the end result. Other times, they are clearly a means to a less noble end.

Will the map show signs of incumbent pressure? Or will it be clear the respect for local governments was not made subservient to incumbent considerations?


At the end of the day, the merits of the map will be proven by the degree to which the Court demonstrates commitment and transparency.

  • The numbers from both district population and local government splits will clearly reveal their commitment to the constitutional framework in the court order.
  • The technical and decision-making information supplied about the court maps will reveal how transparent the Court is willing to be about their venture into district drawing.

The Court has taken extraordinary steps to bring this case to this conclusion. With this culmination comes the expectation of an extraordinarily positive outcome.

Will the Court be forthcoming about why they chose to place the district lines in certain places? Will they remain committed to the standards they’ve laid out? The public is watching and waiting. Good governance hangs in the balance.

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Amanda began delving into the subject of redistricting in October of 2010 on her quest to know why. Helped by a love of puzzles, attention to detail, and a great deal of persistence, her efforts eventually led her to a historic victory before the Pennsylvania Supreme Court. She documents her journey at AmandaE.com, inspiring others through numerous presentations across the state. The recipient of several honors, her work has also been featured in every major Pennsylvania newspaper, making headline news in Pittsburgh and Philadelphia.


  1. Thanks for the analysis! It seems to me priority should be given to keeping counties entire. Counties are substantial historical units that have their own governments, budgets, and political organizations. It is obvious that gerrymandering has lived off county-splitting; to defeat it, the principle of county unity seems even more important than municipal unity. Therefore, I suggest that a county split should count as negatively as, say, 5 or 10 split municipalities.

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