Important information - it's missed by drunken witness (4)
I believe the answer is:
news
'important information' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for news that I've seen before include "Sewn (anag.)" , "Latest information" , "Noteworthy information" , "Important information" , "Information disseminated by the media" .)