Care to get a police warning? (7)
I believe the answer is:
caution
I believe this clue is a double definition.
'care' is the first definition.
('caution' can be a synonym of 'care')
'a police warning?' is the second definition.
(I've seen this before)
'to get' is the link.
(Other definitions for caution that I've seen before include "Care, prudence" , "Prudent wariness" , "Warn strongly" , "Attention to possible danger" , "Caveat, prudence" .)