I understand the definition of "vulnerable adult", but who decides if the person meets the definition or criteria?

A.R.S. § 46-451(A)(10) "Vulnerable adult" means an individual who is eighteen years of age or older and who is unable to protect himself from abuse, neglect or exploitation by others because of a physical or mental impairment. Vulnerable adult includes an incapacitated person as defined in section 14-5101. Read statute for further definition of vulnerable adult. Court may make finding person id vulnerable adult based on statute and facts unique to each matter.