Knossos Games - Gerrymandering

Gerrymandering, otherwise known as redistricting, is a technique used by politicians to gain control over an election's outcome. Forming new voting districts may be done for a variety of legitimate reasons, but can also be used nefariously. The first example was in 1812, when Massachusetts governor Elbridge Gerry made a voting district that looked sort of like a salamander (hence the name).

Congress has tried to regulate redistricting through legislation. Most recently, in 1982, it amended the Voting Rights Act to try and protect the voting rights of racial minorities. However, even under this and other voting laws, states still have a lot of leeway when creating congressional districts, which can lead to gerrymandering.

For the following puzzles, a voting area is being redistricted. Each new district will get one representative to cast a vote for the majority within the district. Your task is to break up the area into the designated number of districts so that the desired outcome of the election is achieved. Each district must be formed by a continuous (edges touching, not just corners) set of sub-districts.

Here are two examples to show how you can influence the results of an election through redistricting:

Here is a voting area that will be broken down into three districts. Notice that, while the total vote count swings in favor of the "Yes" vote, the number of sub-districts swings in favor of the "No" vote.

By dividing the region vertically, the strong "Yes" vote sub-districts are distributed equally among the three districts. This results in each district having a "Yes" majority. This matches the expectations of the overall vote count.

However, by dividing the region horizontally, the strong "Yes" vote sub-districts are isolated into one district. This results in one overwhelming "Yes" district, and two "No" districts.

This is an example of the first method of gerrymandering: concentrating opposition votes so that they are isolated in certain districts. The technical term for this is "packing".

Here is another voting area that will be broken down into three districts. Notice that now both the total vote count and the number of sub-districts swings in favor of the "Yes" vote.

By dividing the region vertically, the three strong "Yes" vote sub-districts are distributed more or less evenly among the three districts, with the two strong "No" vote sub-districts concentrated in one district. This results in two "Yes" districts and one "No" district, which matches the expectations of the overall vote count.

However, by dividing the region horizontally, the strong "Yes" vote sub-districts are isolated into one district, while the slightly weaker "Yes" vote sub-districts are overpowered by the two strong "No" vote sub-districts. This results in one overwhelming "Yes" district, and two "No" districts.

This is an example of the second method of gerrymandering: diffusing votes so that they are simply not strong enough to win certain districts. The technical term for this is "dilution".

Either or both of these methods might be useful in solving the following puzzles.

Finally, I feel it is necessary to put a general disclaimer here. These puzzles are not meant to make anyone good at gerrymandering! Since most voting districts are not square, these puzzles represent an idealized demonstration of how redistricting can work, and the real possibility (and danger) of being able to influence an election through gerrymandering.

Technical and historical information gathered from www.fairvote.org.