The search or raid entry is over; the subjects are secure and being
guarded; and the detectives are gathering their evidence. SWAT’s
portion of the mission would appear to be over. So is it time to stand
down and relax?
Dynamic entries depend on “surprise, shock, and speed” and you go to
the suspects. With deliberate entries like “surround and callout” the
suspects come to you. Knock and announce requirements vary for each
jurisdiction and must be followed.
Remember Murphy's Law. Unexpected obstacles, dogs, darkness, etc., can throw off even the best-laid plans. Effective perimeters don't happen by accident. They require tactics, planning, and precision coordination.