Rule 47.4. Memorandum Opinions

(a) If the issues are settled, the court should write a brief memorandum opinion no longer than necessary to advise the parties of the court’s decision and the basic reasons for it. An opinion may not be designated a memorandum opinion if the author of a concurrence or dissent opposes that designation. An opinion must be designated a memorandum opinion unless it does any of the following: establishes a new rule of law, alters or modifies an existing rule, or applies an existing rule to a novel fact situation likely to recur in future cases;

(b) involves issues of constitutional law or other legal issues important to the jurisprudence of Texas;

(c) criticizes existing law; or

(d) resolves an apparent conflict of authority.