Concerning shooting the pelvis, since it is one of the largest single weight-bearing bones, it is very thick in most places, and a pelvic fracture is usually the result of bone disease or a crushing force that would break practically any other bone in the body. The good news for shooters is that it is built like a box, and if its broken in one place it is usually also broken in another.
The most delicate areas are the hip joints; even if you don't out-and-out destroy the weight-bearing capability of the joint, a bullet and/or bone fragments in the hip is debilitatingly painful and the shattered socket can cause the joint to dislocate. To aim for the hip socket, your shot should be placed below the waistband slightly inside the line of the leg. You have a good chance of severing the femoral arteries or the vena cava with such a shot as well. The pubic bone, located lower and more centrally, forms the front of the pelvis and if broken it is virtually impossible to walk, but such a shot would require pinpoint precision with a very high-speed bullet.
It is interesting to note that this area is actually the true COM of a human being, and virtually anywhere you hit in this area will be critically damaging. hip joints, blood vessels in the intestines and going to the legs, the kidneys, reproductive organs (yes I had to say it) and quite a lot of nerve trunks from the lower spine to the leg trunks are all in this area, and a shot here will likely cripple your attacker for life. However, if your attacker is armed, a shot to this area is not debilitating enough to disable him, or even fully immobilize him. A chest shot, though more protected by ribs, will debilitate the BG much faster as the BG finds themself unable to breathe very quickly with a deflated lung, and very difficult to see when they're bleeding out from the heart or pulmonary arteries.
