Reapportionment is the process of determining how many Congressional seats each state receives.
Redistricting is the redrawing of districts within each state.
Gerrymandering is the manipulation of the redistricting process for political gain.
The Constitution requires that a census be held every ten years to determine the population of each state and that the 435 Congressional seats be reapportioned according to this new data. The Constitution leaves the methods for electing Representatives – including redistricting – up to the individual states. Article I Section IV states:
“The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof; but the Congress may at any time by Law make or alter such Regulations, except as to the Place of Chusing [sic] Senators.”
However, both Congress and the courts have placed certain requirements on the redistricting process:
1. Each district must be equal in population
2. There must be an equal opportunity for minorities to elect the candidate of their choice
So, every ten years, each state is forced to redraw district lines to account for both adjustments in the size of their overall congressional delegation, and variance in the populations of their already-drawn districts. In a few states – Arizona, Hawaii, Idaho, Indiana, Montana, New Jersey and Washington – redistricting is handled by specially appointed bi-partisan commissions. In the rest, control over the path of district lines is controlled by politicians, often those whose political careers might be threatened by the change of a line.
GERRYMANDERING TECHNIQUES
Packing: Placing as many voters of one type in a single district to minimize the number of elections they can influence.
Cracking: Spreading voters of one type over many districts where they will comprise minorities that are unable to influence elections.
Hijacking: Separating an incumbent candidate from his constituents and placing him or her in a district where he or she has no name recognition.
Kidnapping: Drawing two incumbent candidates into the same district so they must run against each other.
GERRYMANDERING SCENARIOS
The Original: Gerrymandering is as old as the country itself. In 1812, Jeffersonian Republicans forced through the Massachusetts legislature a bill rearranging district lines to assure them an advantage in the upcoming elections. Although Governor Elbridge Gerry had only reluctantly signed the law, a Federalist editor is said to have exclaimed upon seeing the new district lines, "Salamander! Call it a Gerrymander." This cartoon-map first appeared in the Boston Gazette for March 26, 1812. Even though the term "gerrymander" originates here, it dates back even further - some say to Patrick Henry drawing Virginia's first Congressional district map so as to make it harder for James Madison to be elected to Congress.
Partisan Gerrymander: When the party in control of the redistricting process draws the district lines to maximize the power of their own party.
Sweetheart Gerrymander: When the people in charge of redistricting tacitly agree to draw district lines to ensure that incumbents of both parties win reelection.
Racial Gerrymander: The drawing of districts to create opportunity for minority voters to elect a candidate of their choice.