Synonymous with the phrase black letter law.
Some examples of judicial usage include Rabang v Canada (Justice Sharlow, Federal Court of Canada, 176 FTR 314, 2000):
"It is trite law that a decision may be quashed on judicial review if the court is unable to find that the opinion had an evidentiary foundation."
Or, the words of Justice Higgins in the Australian case of Munday v Australian Capital Territory (1998 SCACT 62)
"It is trite law and, indeed, a fundamental tenet of the rule of law that the Crown, acting through its executive powers, may not limit or control the otherwise lawful activity of citizens save as permitted by law."
Speaking on the topic of police investigatory powers, the English court said this in PG v The United Kingdom 2001 ECHR 550:
"While it may be permissible to rely on the implied powers of police officers to note evidence and collect and store exhibits for steps taken in the course of an investigation, it is trite law that specific statutory or other express legal authority is required for more invasive measures, whether searching private property or taking personal body samples."