The potential for some really difficult times now exists for officers in the City by the Bay.
Consider a scenario: An officer will hesitate to deem sitting a subject because he or she cannot exactly articulate why his or her spider sense is elevated—something just doesn't feel right, but they just can't put their finger on it. The officer chooses then to keep the suspect standing, handcuffed behind the back. The subject suddenly lunges forward, striking the officer squarely on the nose with a vicious head-butt move. The officer is rendered unconscious.
I won't expound on this hypothetical scenario any further. You get the idea. Very, very bad things can potentially happen. And when it eventually does, I will be the first person to say, "I told you so."
Okay, enough with the theoretical realm—back to the real world.
Sitting subjects on the ground or a sidewalk is a longstanding tactic employed for the safety of both the subject and the officer. Sitting subjects on the ground puts them at a tactical disadvantage, preventing violent attacks on officers or attempts to flee on foot. Even handcuffed subjects are potentially dangerous to an officer, especially a cop who is working alone.