Purcell principle

In United States law, the Purcell principle is the doctrine that courts should not change election rules too close to an election, because of the risk of causing confusion. It is named after Purcell v. Gonzalez, a 2006 case from the U.S. Supreme Court’s emergency docket, or shadow docket. It is frequently invoked by the Supreme Court and lower courts to allow elections to proceed under a state’s preferred voting requirements, maps, and other rules. Parameters for what constitutes an applicable change in election rules or when is too close to an election have never been laid out, an ambiguity that allows the Supreme Court to invoke it selectively.