No you can't. If you get it below the spine you are going to hit lung. What Rob/PA said, may not be much but there is not enough room to get a broadhead through there without hitting lung.

wolfhound, what likely happened there was the client hit high, going through the backstraps and also hit the dorsal spinous process breaking it off. This will shock the spinal cord/column and make the animal go down. As soon as the shock factor in the cord wears off, happens very quickly, the animal will get up and run away.