Rejig nothing without judge's rule (5)

I believe the answer is:

reign

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'rule' is the definition.
(I know that reign is a type of rule)

I cannot understand how the rest of the clue works.

(Other definitions for reign that I've seen before include "Monarch's period" , "Wield the sceptre" , "Sovereign's rule" , "Rule - dominate" , "Period of the rule of a sovereign" .)

I've seen this clue in the Sydney Morning Herald.

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