Copper heard round a northern district daily initially? That's beyond doubt (3,3,5)
I believe the answer is:
cut and dried
'beyond doubt' is the definition.
(cut and dried means clear or beyond doubt)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for cut and dried that I've seen before include "to have it [HAIRSTYLE] so treated?" , "prearranged" , "Two things the hairdresser did" , "Tobacco has to be" , "Decided in advance" .)