On Monday, the U.S. Supreme Court upheld Arizona’s congressional map as drawn by an independent redistricting commission. The 5-4 ruling could have significant ramifications moving forward as various states consider the use of independent commissions to draw congressional districts.

In 2000, Arizona voters adopted the use of an independent commission, which redrew district lines for the 2002 election and again for the 2012 election. The Republican-led state legislature challenged the 2012 map, which was upheld in federal district court. This week’s ruling by the Supreme Court has an immediate effect on Arizona as well as California, where it is widely speculated that the Democratic-led state legislature would have redrawn its state lines had the Supreme Court overturned this ruling.

Following each 10-year census, reapportionment moves a handful of congressional districts from states that have lost population to states that have gained population relative to the overall growth in the country. Redistricting—the process of drawing new electoral district boundaries— is then up to the state. The majority of states rely upon the state legislature to perform this duty, while a handful of others (currently Arizona, California, Hawaii, Idaho, New Jersey and Washington) rely upon independent commissions. Several states use a hybrid of the two or have only one congressional district.

This week’s decision will embolden some groups to push for more independent election commissions to be adopted via state ballot measures. Regardless of that outcome, one thing remains certain: Election years ending in a zero are at a premium since the resulting state legislatures by and large draw new district maps. Look for the next such bellwether election to take place in 2020, which will coincide with a Presidential election and is expected to have a larger turnout than the 2010 election.

Nathan Riedel is Big “I” vice president of political affairs.