Voter caging refers to challenging the registration status of voters and calling into question the legality of allowing them to vote. Sometimes, it involves sending direct mail to the addresses of registered voters and compiling a list of addressees from which the mail is returned undelivered. The list is then used to purge or challenge voters' registrations on the grounds that the voters do not legally reside at the registered addresses.
In the United States, the practice is legal in many states. However, it has been challenged in the courts for perceived racial bias, and it has been declared illegal under the Voting Rights Act of 1965.
The term has also been applied to recent cases of increased requirements for proof of identity, residency, and eligibility being added with the intent to limit the number of eligible voters.
Voter caging typically refers to the practice of sending mail to addresses on the voter rolls, compiling a list of the mail that is returned undelivered, and using that list to purge or challenge voters' registrations and votes on the grounds that the voters on the roll do not legally reside at their registered addresses.
Usually, a political party will send out non-forwardable, first-class mail to voters or particular voters they want to target (often assumed to be a demographic that belongs to the opposing party). It will compile a list of voters for whom mail has been returned as undeliverable. The list is called a caging list. In some cases, such mail can be returned at a rate of 1 in every 15 letters sent out, as shown in Ohio in 2008 when the Board of Elections had 600,000 letters of voter confirmation returned as undeliverable. The party uses caging lists created by themselves or by the Board of Elections to challenge the registration status of voters and potentially purge them from the voting rolls under state laws that allow voters whose registrations are suspect to be challenged.
When voters turn out to vote, they may be challenged and required to cast a provisional ballot. If investigation of the provisional ballot demonstrates that the voter has just moved or there is an error in the address and the voter is legally registered, the vote should be counted as well as vice versa.
Section 8 of the National Voter Registration Act of 1993 (NVRA) has been interpreted to prohibit voter caging:
"Pursuant to the NVRA, a voter may not be removed from the voters list unless (1) the voter has requested removal; (2) state law requires removal by reason of criminal conviction or mental capacity; (3) the voter has confirmed in writing that he has moved outside the jurisdiction maintaining the specific voter list, or (4) the voter both (a) has failed to respond to a cancellation notice issued pursuant to the NVRA and (b) has not voted or appeared to vote in the two federal general elections following the date of notice."