Law students learn early about the differences between majority, concurring, and dissenting opinions. But those aren't the only types of opinions that lawyers see. As a law student and young lawyer, I was often confused about the less common types of opinions and what, if any, precedential value they have. Here's an explanation of some opinions you might see:
En banc opinions—An en banc opinion is one issued by all members of an appellate court, rather than a panel of judges. A litigant dissatisfied with a panel's opinion may petition for an en banc hearing. The petition for an en banc hearing may only be granted by a majority of judges. Occasionally, a court will decide at the outset that an en banc hearing is necessary because an issue is of such importance that it should be heard by the full court.
Memorandum opinions—These opinions are unpublished but almost always unanimous. They generally are short and contain little explanation or analysis. Memorandum opinions are usually reserved for cases where the law is well-settled. They may be as short as a single sentence or two. Often memorandum opinions are unpublished and provide little, if any, precedential value given the lack of thorough explanation of the court's ruling.
Panel opinions—Panel opinions are the most common opinions and are issued by a panel of judges rather than a full court. For example, cases heard by the Court of Appeals of Georgia are heard by three-judge panels. Three-judge panels are common in many courts, including the United States Circuit Courts. Litigants dissatisfied with a panel opinion may petition for a hearing en banc.
Per curiam opinions—Per Curiam opinions are perhaps the oddest of all opinions. Most are like memorandum opinions in that they are usually short with little explanation or analysis on well-settled areas of law. But per curiam opinions differ in that they are issued by the court as a whole rather than signed by a particular judge—thus, the author is unknown. Per curiam opinions are usually unanimous, but not always. For example, Bush v. Gore, 531 U.S. 98 (2000) was a per curiam opinion in which Chief Justice Rehnquist concurred and Justices Stevens, Souter, Ginsberg, and Breyer dissented. Some legal scholars have called for an end to per curiam opinions, arguing that they reduce judicial accountability and stunt the development of law.
Plurality opinions—Plurality opinions result when no single opinion receives majority support. The plurality opinion is the one that receives the most support, but not majority support. Plurality opinions are interesting in terms of their precedential value. If there’s no majority opinion, are they persuasive only? According to Marks v. United States, 430 U.S. 188 (1977), when the court is “fragmented” and “no single rationale explaining the result enjoys the assent of [a majority], the holding of the [c]ourt may be viewed as that position taken by those Members who concurred in the judgments on the narrowest grounds.” Id. at 193. But what does that really mean? Obviously, the opinion should be read narrowly, but as with many areas of law, there are multiple schools of thought on how to apply the Marks rule.