Country involved in formal investigation (4)

I believe the answer is:

mali

'country' is the definition.
(Mali is an example)

'involved in formal investigation' is the wordplay.
'involved in' indicates a hidden word.
'MALI' is hidden in the letters of 'formal investigation'.

(Other definitions for mali that I've seen before include "Land" , "African country, once French Sudan" , "Country of West Africa" , "part of Africa" , "West African country, capital Bamako" .)

I've seen this clue in The Guardian.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.