case in point vs instance

case in point and instance both are nouns.

Word	Noun	Adjective	Verb	Adverb
case in point	Yes	No	No	No
instance	Yes	No	Yes	No

As nouns, instance is a hypernym of case in point; that is, instance is a word with a broader meaning than case in point:

case in point: an example that is used to justify similar occurrences at a later time
instance: an item of information that is typical of a class or group

Other hypernyms of case in point include example, illustration, representative.

case in point (noun)	instance (noun)
an example that is used to justify similar occurrences at a later time	an item of information that is typical of a class or group
	an occurrence of something

case in point (verb)	instance (verb)
	clarify by giving an example of