A large bird provides proofs of innocence (6)
I believe the answer is:
alibis
'proofs of innocence' is the definition.
The answer and definition can be both related to communication as well as being plural nouns.
Maybe they are linked in a way I don't understand?
'a large bird' is the wordplay.
'large' becomes 'L' (eg in clothes sizes).
'bird' becomes 'ibis' (ibis is a kind of bird).
'a'+'l'+'ibis'='ALIBIS'
'provides' is the link.
Can you help me to learn more?
(Other definitions for alibis that I've seen before include "Pleas of being elsewhere at the time of a crime" , "Defences - was elsewhere at time of crimes" , "Excuses" , "Defences of being elsewhere at the time of a crime" , "Legal defences of being somewhere else at times of crimes" .)