In the United States, can the distribution of congressional representatives be adjusted in response to dramatic population shifts?
In the United States, elections are run by state governments. Each state is allotted a certain number of congressional representatives based on its population. The population of each state is determined by the census taken once every 10 years. The number of congressional representatives a state has both determines the number of representatives that state holds in the US House of Representatives and the number of electors allotted to each state in the Electoral College.
As an example, the State of New York had a population of 19,378,102 in the 2010 census. The Census Bureau allotted the State of New York 27 seats in the House of Representatives. With 2 seats in the Senate, the State of New York has 29 total electors in the 2020 Electoral College.
Now suppose that after the census was taken, a dramatic event happened that significantly and permanently shifted the population distribution among the States. I provide some examples below:
- A Nuclear Power plant explodes making a big city uninhabitable.
- Immigration law changes leading to a dramatic influx of new immigrants to coastal or border states like Washington, California, Texas, or New Mexico.
- A natural disaster like The Big One kills millions of residents.
If an event like one of these occurred, the true population of each state would no longer resemble the estimated population of each state from the Census. One might suspect that there would be calls to adjust population estimates in response to the disaster.
Has something like this happened before? Are there laws in place that would allow adjustments to population estimates in-between the 10-year censuses? If so, at what point of the election cycle would those adjustments be made?