Connected case to said criminal (10)
I believe the answer is:
associated
'connected' is the definition.
(synonyms)
'case to said criminal' is the wordplay.
'criminal' is an anagram indicator.
'case'+'to'+'said'='casetosaid'
'casetosaid' anagrammed gives 'ASSOCIATED'.
(Other definitions for associated that I've seen before include "Made a logical or causal connection" , "Connected (with)" , "Linked" , "Went about with" , "in a group, perhaps" .)