When on patrol, I always wear my seatbelt. However, there are times when it is tactically necessary to take it off. I take it off whenever I am checking behind a business or going through an alley in case I am surprised by someone and need to exit my vehicle quickly. I also take it off about two blocks away from a call that I am responding to for the same reason.
It is also a good idea to take off your seatbelt before you initiate a traffic stop. It would be a lot easier to re-apply your seatbelt if a pursuit ensues than it would be to take it off quickly if the suspect jumps out with a weapon.
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