We often see in a court context sentences like "Hear the matter of xxx vs. xxx". But in newspapers, you see "hear the case of xxx vs xxx" too. Is the former legal language whereas the latter non-legal language? Or is there a difference between the two? Thanks.
'In the matter of' is a translation of the Latin re. (This is relevant because for many years Latin was the main legal language - which is why legal terminology is scattered with Latin phrases like prima facie and habeas corpus.)
A matter of concern or discussion or activity of some kind for lawyers doesn't always lead to a court case. The legal matters reported in newspapers, however, often are court cases. So, prima facie (on the face of it/at first glance), I'd expect lawyers to use both words and journalists to use 'case' (which has the added benefit, for journalists, of being shorter - more appropriate for use in headlines and in text when the column is narrow).
b