Lofty dwelling identified by detective crossing Rhode Island (5)
I believe the answer is:
eyrie
'lofty dwelling' is the definition.
(I've seen this before)
'detective crossing rhode island' is the wordplay.
'detective' becomes 'eye' (as in a private eye).
'crossing' is an insertion indicator (to cross can mean to go over or around).
'rhode island' becomes 'RI' (US postal abbreviation).
'eye' going around 'ri' is 'EYRIE'.
'identified by' is the link.
(Other definitions for eyrie that I've seen before include "Inaccessible place" , "elevated position" , "retreat for hunter" , "home of 12 [RAPTOR]" , "Lofty home" .)