In law, a memorandum opinion is usually an unpublished legal opinion that cannot be cited as precedent. It is formally defined as: " unanimous appellate opinion that succinctly states the decision of the court; an opinion that briefly reports the court's conclusion, usu. without elaboration because the decision follows a well-established legal principle or does not relate to any point of law."  There is no elaboration or explanation because the decision either follows a well-known legal principle or it does not relate to a point of law. A memorandum opinion is also not subject to appeal.
|Judicial opinions & aggregates for official decisions (O.S-Federal)|
Generally, memorandum opinions follow ordinary rules, including the application of precedent and the rule of stare decisis.