Statement FIFA put out: US lawyer against it (9)
I believe the answer is:
affidavit
'statement' is the definition.
(affidavit is a kind of statement)
'fifa put out us lawyer against it' is the wordplay.
'put out' indicates anagramming the letters.
'us lawyer' becomes 'D.A.' (abbreviation for District Attorney).
'against' becomes 'v' (abbreviation for 'versus').
'fifa' anagrammed gives 'affi'.
'affi'+'da'+'v'+'it'='AFFIDAVIT'
(Other definitions for affidavit that I've seen before include "Declaration before notary" , "Written declaration made under oath" , "Sworn court statement" , "Instrument's" , "Legal declaration" .)