# Purcell Principle The judicial practice of declining to change election rules — including district maps — as an election draws near, on the theory that late changes confuse voters and burden administrators. It takes its name from *Purcell v. Gonzalez* (2006), a brief unsigned Supreme Court opinion about an Arizona voter-ID rule. **It is not a rule with a defined deadline.** No statute or opinion fixes how near is too near, so in practice the principle operates as a timing defense that can be invoked at a court's discretion. Its structural effect in redistricting litigation is that a plaintiff can be right on the merits and still lose, because the calendar has run — and because the election then proceeds under the map that was challenged. See [[Rucho v. Common Cause]] and [[Gerrymandering]].