Overt criminality that leaves us in the dark? (8,7)

I believe the answer is:

daylight robbery

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'dark?' is the definition.
Both the answer and definition are singular nouns.
Maybe they are linked in a way I don't understand?

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for daylight robbery that I've seen before include "as shoplifting usually is" , "Scandalous" , "A shameless swindle" , "Extortion" , "Blatant overcharging" .)

I've seen this clue in The Times.

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