Defective legal procedure? There’s one in the wind (8)
I believe the answer is:
mistrial
'defective legal procedure?' is the definition.
'there's one in the wind' is the wordplay.
'there's one' becomes 'i' (I can't explain this - if you can you should give a lot more credence to this answer).
'in the' indicates putting letters inside.
'wind' becomes 'mistral' (mistral is a kind of wind).
'i' put into 'mistral' is 'MISTRIAL'.
(Other definitions for mistrial that I've seen before include "legal process going wrong" , "damaged hearing?" , "Failed court action" , "Court case invalidated by procedural error" , "Court hearing invalidated by error" .)