Tennessee is divided into nine U.S. Congressional districts, 33 state senate districts and 99 state house districts.
But who draws the boundary lines? Who decides that the 4th Congressional district is over here and that the 18th state senate district is over there?
The short answer is that the Tennessee General Assembly draws the lines through a process called "redistricting."
Here are some important things to know about redistricting in Tennessee:
* Every piece of land in Tennessee can only be located in one Congressional district, state senate district and state house district. (That way a person can't vote in more than one state House district.)
* Every registered voter in Tennessee has a voter registration card which tells them where to vote on election day and in what Congressional, state senate and state house district in which they vote. Each voter registration card also tells them in what local districts they live in (see example, to the right).
* According to federal law, every Congressional district, state senate district and state house district must have roughly the same number of people as all the other districts. So, since Tennessee has a current population of 6.4 million, and since there are 33 state senate seats, each state senator represents about 6.4 million divided by 33, or about 194,000 people.
* Because people move, and because some parts of the state grow in population more than others, district lines have to be redrawn once every ten years. The redistricting process begins when the U.S. Census Department releases its data (which it does every year ending with zero) and takes about a year.
* The last time district lines were redrawn was in 2011-12, in advance of the elections that took place on November 6, 2012.
Over time, redistricting can result in important changes to what parts of the state elected officials come from. It can also affect how many members of the U.S. House of Representatives there are from Tennessee.
Here are some examples of this:
* In the 1970s, Tennessee had only eight Congressional districts. Because of population growth, Tennessee got a ninth district in 1980, and continues to have nine.
* In 1986, there were THREE state House districts combined from Rutherford and Williamson counties (these are the counties immediately southeast and south of Nashville). In recent years, Rutherford and Williamson have consistently been the two fastest growing counties in Tennessee. District lines were redrawn in 1991, 2001, and 2011, each time giving those counties increased representation because of population growth. Today, there are SEVEN House members from these two counties combined!
* Meanwhile there are counties all over Tennessee that used to have their own House member, but who now have to share a House district because those areas have stagnant or even decreasing population. For example, Shelby County had 18 House districts in the 1970s, but only 14 today.
So how does the process really work?
After the U.S. Census data comes out, leaders of the Tennessee House and Senate spend several months studying the data with the staff attorneys of the Tennessee General Assembly to come up with new district lines.
After this process, the leadership of the House and Senate releases their planned new district lines. (This is a big deal, because many elected officials discover, on the day that the planned district lines are released, that they will probably not be re-elected.) Both chambers then vote the new districts into law, typically early in the legislative session.
At the same time that new district lines are being drawn statewide, every county government in Tennessee also has to redraw its district lines. This process is overseen by the Tennessee Comptroller's office.
Now for a few other points about redistricting:
* It has been said before that the political party with a majority of the members of the House or Senate during redistricting can use the process of redistricting to solidify its hold on power (a process known as gerrymandering). No doubt this is true. However, the degree to which this occurs is a matter of opinion.
Currently, the Republicans are in control of both houses of the Tennessee legislature. Some Democrats accused them of gerrymandering when the new district lines were announced in January 2012. In previous decades, the Democrats were in control of both houses of the Tennessee legislature. Republicans accused them of gerrymandering when district lines were redrawn in 1981, and 1991, and 2001.
* Federal law requires all states to redistrict every 10 years. That didn't used to be the case. In fact, the state of Tenneseee did not redistrict a single time between 1901 and 1961, a time period during which there was a big shift between rural and urban areas of the state. A landmark U.S. Supreme Court case (which started in Tennessee) called Baker v. Carr changed all that, which is why redistricting now occurs every 10 years.
* Besides the Baker v. Carr lawsuit, the other major turning point that affected the way district lines were drawn in Tennessee was the Voting Rights Act of 1965.
Prior to the voting rights act, cities such as Memphis and Nashville did not have separate House districts. Instead, each city had a certain number of House seats, and the House members were all elected "at large." So if Nashville had, say, 10 House seats, then the 10 candidates who got the highest number of votes won.
The use of "at large" districts in urban areas effectively kept African Americans from serving in the House. After the Voting Rights Act, the courts ordered states such as Tennessee to draw separate district lines for all 99 House seats.
In 1965-66, there was only one African-American member of the Tennessee State House. In 1966-67, that number jumped to six.
* If, through the process of redistricting, a group of people feels as if district lines were drawn in a manner that violates their Constitutional rights, they can file suit against the state and ask the courts to force the state to redraw the lines. A few years ago, for instance, a lawsuit called Rural West Tennessee African-American Affairs Council v. Sundquist led to the creation of a predominantly African-American district in West Tennessee (outside of Memphis). Today that is District 80, represented by Rep. Johnny Shaw of Jackson.
* Historically, Tennessee governors have stayed clear of the redistricting process.