question of law vs matter of law

question of law and matter of law both are nouns.

Word	Noun	Adjective	Verb	Adverb
question of law	Yes	No	No	No
matter of law	Yes	No	No	No

As nouns, question of law and matter of law are synonyms defined as:

question of law and matter of law: a disputed legal contention that is generally left for a judge to decide

question of law (noun)	matter of law (noun)
a disputed legal contention that is generally left for a judge to decide	a disputed legal contention that is generally left for a judge to decide