The most common and most likely answer to this crossword clue is the 9 letter word DATELINES
I've seen this crossword clue in The Daily Telegraph
D
A
T
E
L
I
N
E
S
Buddy explains!
The straight part
We know that "leading items" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case leading items = datelines.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 DATELINES mean?
DATELINES noun- A line at the beginning of a document (such as a newspaper article) stating the place of origin and typically the date, and often written in capital letters.