As glacial said, its the server tickrate, according to your client the police officer is there, but according to the server due to a slow refresh he is still to the left in the center of your scope most likely
Shots 1-5: Clearly missed.
Shots 6-9: Missed due to recoil (bad spray control).
Shots 10-11: Very close, but recoil and inaccuracy make these reasonable misses.
Shot 12: Likely didn't actually fire because PERP is already dead.
welcome to the world of interp and other Source networking spaghetti