Bank account details the police may take (9)
I believe the answer is:
statement
'police may take' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'bank account details the' is the wordplay.
'bank' becomes 'state bank' (state bank is a kind of bank).
'account details' becomes 'men' (I can't explain this - if you can you should believe this answer much more).
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'state'+'men'+'t'='STATEMENT'
Can you help me to learn more?
(Other definitions for statement that I've seen before include "revelation" , "Account given to a court" , "It's made, about account say" , "Formal (court) account" , "Financial summary" .)