When there's a change of plea men select a jury (7)
I believe the answer is:
empanel
'select a jury' is the definition.
'empanel' can be an answer for 'select' (empaneling is a kind of selecting). I am not sure about the 'a jury' bit.
'when there's a change of plea men' is the wordplay.
'plea men' can be anagrammed to 'EMPANEL'.
But, I'm not sure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for empanel that I've seen before include "Make a juror" , "Select for jury service" , "Enrol (a jury)" , "Men leap (anag.)" , "select jurors" .)