Human support by nearly everybody is allowed in court (5)
I believe the answer is:
legal
'allowed in court' is the definition.
'legal' can be an answer for 'allowed' (I've seen this before). I am not certain of the 'in court' bit.
'human support by nearly everybody' is the wordplay.
'human support' becomes 'leg' (leg is a kind of support. I am not sure about the 'human' bit.).
'by' means one lot of letters go next to another.
'nearly' means to remove the last letter.
'everybody' becomes 'all' (all people).
'all' with its last letter taken off is 'al'.
'leg'+'al'='LEGAL'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for legal that I've seen before include "Authorised" , "sanctioned" , "Observing acts" , "Rightful" , "Street - (1978 Dylan album)" .)