law: Marine Insurance Act, 1963 
  48. Deviation
  (1) Where a ship,
  
  without lawful excuse, deviates from the voyage contemplated by the policy, the
  
  insured is discharged from liability as from the time of deviation, and it is
  
  immaterial that the ship may have regained her route before any loss occurs.
  (2) There is a
  
  deviation from the voyage contemplated by the policy-
  (a) where the course of the voyage is
  
  specifically designated by the policy, and that course is departed from; or
  (b) where the course of the voyage is not
  
  specifically designed by the policy, but the usual and customary course is
  
  departed from.
  (3) The intention to
  
  deviate is immaterial; there must be a deviation in fact to discharge the
  
  insurer from his liability under the contract.