From beginning to end this screen grab sequence of the Officer in McKinney Texas is less than 6 seconds. Six seconds inside the threat matrix. This is what police have to deal with.
Never run up behind a cop dealing with a volatile situation:
Decisions needing to be made in micro-seconds. Again, this entire sequence is less than 6 seconds in real time video.
Notice the officer never actually points his firearm at anyone. After unholstering it and securing it in his hand he keeps the hand gun pointed down toward the ground until re-holstered.
Watch it again: