Declare to be in doubtful taste (5)
I believe the answer is:
state
'declare' is the definition.
(I've seen this before)
'doubtful taste' is the wordplay.
'doubtful' is an anagram indicator.
'taste' with letters rearranged gives 'STATE'.
'to be in' acts as a link.
(Other definitions for state that I've seen before include "Government; say" , "See 18" , "Declare - political unit" , "See 3" , "Speak" .)