Plain error is error that is plainly evident from the record and affects a litigant's substantial right(s). Although an appellate court generally only reviews errors brought to its attention by the litigants, it has the discretion to correct plain errors that were not addressed, or forfeited, when not doing so would affect the integrity and reputation of the courts. However, this power is permissive and not mandatory. Plain errors are often the issue in Criminal procedure. Under the Federal Rules of Criminal Procedure Rule 52, "a plain error that affects substantial rights may be considered even though it was not brought to the court's attention." The purpose of the plain error rule is not only to protect the defendant from serious injustices, but to also protect the reputation of the courts and ensure that their decisions follow a fair procedure.
In determining whether there is a plain error under Rule 52, the Supreme Court has articulated the following 4-prong test:
- First, there must be an error or "deviation from a legal rule" that has not been affirmatively waived by the appellant.
- Second, the error must be "plain," "clear," or "obvious," such that it cannot be reasonably contested.
- Third, the error must have affected the appellants substantive rights, meaning that it must be shown that it was prejudicial or affected the outcome of the lower court's proceedings. The defendant has the burden of persuasion to show such prejudice.
- Lastly, if the first three prongs are satisfied, then the appellate court has the discretion of correcting the error only if the error seriously affects the fairness, integrity, or public reputation of judicial proceedings.
For example, a miscalculation of a defendant's sentence, resulting in a sentencing that is longer than necessary, has been found to be a plain error requiring correction from appellate court. In addition, if the law changes such that a plain error can be found at the time of appellate review, but no plain error existed at the time of the lower court's proceedings, the appellate court still has the authority to correct such an error. Rule 52 also differentiates between plain errors and harmless errors. Unlike plain errors, harmless errors are ones that do not affect substantial rights and must therefore be disregarded if not contested.
[Last updated in July of 2020 by the Wex Definitions Team]