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Redistricting Principles

In Redistricting Beauty is in the Eye of the Court

Traditional Redistricting Principles

Illinois' 4th Congressional District drawn during the 1990's decade of redistricting was ultimately upheld by courts against racial gerrymandering claims. The reason: it was necessary to avoid minority vote dilution in the Chicago area.


King v. State Board of Elections, 979 F. Supp. 619 (N.D. Ill. 1997), aff'd mem. 118 S. Ct. 877 (1998).


How To Draw Redistricting Plans That Will Stand Up in Court (Peter S. Wattson, 2011) (pdf)


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What are Traditional Redistricting Principles?


 Traditional Redistricting Principles
 The Original Gerrymander
Gov. Elbridge Gerry (MA), 1812


Since the decennial practice of redistricting began after the landmark case Baker v. Carr required equally populated political districts, the process of redrawing district lines for that purpose has generated a set of “traditional” principles or criteria. Each of the criteria below has been recognized by courts (including the Supreme Court) as desirable or at least permissible to abide by when redrawing district lines. All 50 states require at least one of these principles in state law.




Compactness is one of the most basic principles for drawing political districts. Indeed, it just may be the oldest principle as evidenced by the uproar of Elbridge Gerry’s district in 1812.[1]  Courts have recognized this principle in several cases expressly noting that “compactness does have to be one of [redistrictings’] primary goals.”[2]  More recently, compactness has played a central role in minority vote dilution claims and is a key issue in the line of racial gerrymandering cases sparked by the Supreme Court’s Shaw v. Reno decision.[3]


Compactness refers to a districts’ geographic shape and how its interior is dispersed within its boundaries. For instance, a circle is considered to be a perfectly compact shape. In redistricting, the notion of compactness is difficult to evaluate because the line drawer rarely begins with a perfectly compact shape to place districts in. That is, many states and localities already have irregularly shaped borders and boundaries. Moreover, the principle of compactness must compete with other important principles which are discussed below. Thus, the determination of whether a district violates the compactness principle is a complex process based on the interplay of many factors other than geometric shape.




Contiguity simply requires that all parts of a district be physically connected. Practically speaking, it is a district in which one can travel to all parts of without crossing its border.[4] Most state constitutions require contiguity along with compactness in their congressional and legislative districts.[5] Congress had required in its own internal rules contiguity for congressional districts as early as 1842,[6] compactness was required in the Reapportionment Act of 1911[7], but subsequent revisions of the U.S. Code eliminated the language. Courts however have made it clear that contiguity is a de facto requirement for districts provided the geography in question does not include islands.[8]


Contiguity, like compactness can be a matter of degree. Districts can be drawn that are contiguous by way of water or bridge, and two areas of a district may only be contiguous by a small point. Some state constitutions are specific about whether or when water or point contiguity is allowable.


Preserving Local Political Subdivisions


Language aimed at minimizing the crossing of city, county, town, and other municipal boundaries is second only to contiguity requirements in state constitutions[9]. Local subdivisions are profoundly affected by the legislative and congressional boundaries they reside in. To promote unity within localities, states seek to minimize splitting subdivisions among several districts whenever possible. Redistricting plans that do split local subdivisions excessively are generally deemed inferior and in some cases, evidence of unconstitutional gerrymandering.[10]



Preserving Communities of Interest


Communities of interest is perhaps the least measurable and most subjective of court recognized traditional districting principles. At least 21 states expressly encourage in their constitutions or statutes; maintaining communities of interest when redrawing district lines.[11] There is no formal definition for the term except to say that it refers to readily identifiable communities of like-minded individuals. The Supreme Court refers to “communities that have some common thread of relevant interests.[12]” As a practical matter, this goal is usually subordinated to the previous three principles.



Protecting Incumbents and the Cores of Prior districts


Incumbency protection and the closely related objective of maintaining the cores of previous districts are considered an allowable political consideration by courts, but only on a cautionary basis.[13] The rationale is that incumbents made to run against each other in newly drawn districts – while unavoidable in some cases – is disruptive to the political process when done excessively. Preserving the inner cores of districts is also considered to be less disruptive to the voter inside of those districts.


These two principles are almost always subordinated to the previous principles and there is much disagreement on whether incumbents should be considered in the line drawing process. Moreover, there are various arguments against the preservation of a districting scheme that is inferior, gerrymandered, or otherwise objectionable. Thus, these two principles stand on the least firm ground both in practice and in the law.


[2] Stone v. Hechler, 782 F. Supp. 1116, 1127 (N.D. W. Va. 1992.

[3] Shaw v. Reno, 509 U.S. 630 (1993). Reynolds v. Simms, 377 U.S., at 578, (recognizing compactness, contiguity and integrity of political subdivisions as legitimate state interests).


[4] Matter of Sherrill v. O’Brien, 188 N.Y. 185, 207 (1907).

[5] Redistricting Law 2010, 107, National Conference of State Legislatures, Wash. D.C.(2010).

[6] Lewis Deschler and Wm. Holmes Brown, 2 Deschler-Brown Precedents of the United States House of Representatives, Ch. 8 § 1. (1974).

[7] Reapportionment Act, 37 Stat. 13 (1911).

[8]  Shaw v. Reno, 509 U.S. 630, 647 (1993).

[9] Redistricting Law 2010, 107, National Conference of State Legislatures, Wash. D.C.(2010).

[10] Gomillion v. Lightfoot, 364 U.S. 339 (1960), (involving a tortured municipal boundary line drawn to exclude black voters).

[11] Redistricting Law 2010, 107, National Conference of State Legislatures, Wash. D.C.(2010).

[12] Miller v. Johnson, 515 U.S. 900 (1995).

[13] Abrams v. Johnson, 521 U.S. 74 (1997).