My mistake. Watching the video again it was actually a stop sign and not a red light.
Here is when it occurred.
The guy approaches the stop sign, but didn't come to a full stop, you can see he does brake, indicates that he's turning left, could see no one coming and does turn left. More like a braking/rolling stop and turns left but not completely stopping. Cops probably left their ticket book at the station and went straight in for the kill. No judge, no jury, straight for the gun and the kill.