Systematic police search (7)
I believe the answer is:
dragnet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">systematic police search</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for dragnet that I've seen before include "Systematic police search for wanted person" , "Granted, this may be an organised system of gathering in" , "Granted (anag.); police search" , "Systematic search (for criminals)" , "hunt for suspect" .)