In an appropriate case

The term “in an appropriate case” has already been clarified by this Court in Almonte v. Vasquez,[21] thus –

Rather than referring to the form of complaints, therefore, the phrase “in an appropriate case” in Art. XI, §12 means any case concerning official act or omission which is alleged to be “illegal, unjust, improper, or inefficient.”

http://sc.judiciary.gov.ph/jurisprudence/2002/apr2002/115103.htm