"New Australian university trusts in legal principals", states Cephalopod (8)
I believe the answer is:
nautilus
'cephalopod' is the definition.
(nautilus is a kind of cephalopod)
'new australian university trusts in legal principals states' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'australian' becomes 'A'.
'principals' indicates taking the first letters.
'states' becomes 'US' (abbreviation for the United States).
The first letters of 'university trusts in legal' is 'util'.
'n'+'a'+'util'+'us'='NAUTILUS'
(Other definitions for nautilus that I've seen before include "Sea creature to be found in the usual tin, unusually" , "Nemo's sub (Verne)" , "Spiral-shelled mollusc" , "'Pearly' mollusc" , "Cephalopod mollusc" .)