Yes ... they are trained to shoot for "center mass", because that's the largest part of your body.
Unless they have sniper training, then they are taught to shoot for the head as well. Because shooting someone in the head will prevent them from doing something like triggering a bomb or killing a hostage.
Why aren't regular police taught to be expert marksmen?
Because it would require a LOT more training time and money.
Also, when you are in a high-stress situation, it's easier to aim for the largest target area.
Even then, think of how many bullets are actually fired - vs how many hit the target - when police DO use their weapons; and you will understand that police officers are notoriously bad shots in the field, compared to when they do target practice.