The most common and most likely answer to this crossword clue is the 2 plus 6 letter word ON RECORD
I've seen this crossword clue in Independent
O
N
R
E
C
O
R
D
More clues leading to the result ON RECORD
- . Coroner beginning to doubt suspect is publicly known
- Or Corden’s balls-up, available for public view?
- Odd trace of drugs coroner officially documented
- Coroner ordered date to be officially acknowledged
- Coroner ordered date to be publicly known
- Terrible crooner died, it’s official
- Publicly known to be working with criminal history
- Coroner corrupted Queen’s file in the official protocol
- Official musician’s name might be displayed so?
Buddy explains!

The straight part
We know that "officially documented" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case officially documented = on record.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.