The most common and most likely answer to this crossword clue is the 6 letter word RENVOI
R
E
N
V
O
I
Buddy explains!
The straight part
We know that "Turning over cases primarily national and international" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case turning over cases primarily national and international = renvoi.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RENVOI mean?
RENVOI noun- A situation in which a court, tasked with deciding which state's law should apply to a case, decides to apply the law of the forum, based on the determination that a court from another involved state would also apply the law of the forum.
- Cross-reference in text; a sign that refers to something introduced earlier in a text.