Insinuated the mischievous child didn't tell the truth (7)
I believe the answer is:
implied
'insinuated' is the definition.
(I've seen this before)
'mischievous child didn't tell the truth' is the wordplay.
'mischievous child' becomes 'imp' (imp can mean a misbehaving child).
'didn't tell the truth' becomes 'lied' (I've seen this in another clue).
'imp'+'lied'='IMPLIED'
'the' acts as a link.
(Other definitions for implied that I've seen before include "Understood" , "I limped in hinted or suggested way" , "State indirectly" , "Stated indirectly" , "Insinuated, hinted" .)