Lies bound to be rejected outside European Commission (6)
I believe the answer is:
deceit
'lies' is the definition.
'bound to be rejected outside european commission' is the wordplay.
'bound' becomes 'tied' ('tie' can be a synonym of 'bind').
'to be rejected' says the letters should be written backwards.
'outside' indicates putting letters inside.
'european commission' becomes 'ec'.
'tied' reversed gives 'deit'.
'deit' placed around 'ec' is 'DECEIT'.
(Other definitions for deceit that I've seen before include "Duplicity or trickery" , "Chicanery" , "Fraud, falseness" , "Pretence, cheating" , "Fraud, falsity" .)