(2) The use of deadly physical force in the execution of a search warrant is justifiable only:
(a) If the officer reasonably believes that there is a substantial risk that things to be seized will be used to cause death or serious physical injury if their seizure is delayed and that the force used creates no substantial risk of injury to persons other than those obstructing the officer; or
(b) If the officer reasonably believes that the use of deadly physical force is necessary to defend the officer or another person from the use or threatened imminent use of deadly physical force. [1973 c.836 §89]