In twilight how were Edward and Emmett able to kill James?

. He helped weakened him, but didn't kill him. Emmett, Jasper, and Alice killed him. Alice started the fire with the floorboard, Emmett and Jasper teared James to shreds and threw the piece into the fire. Alice Ripped His Head Off. All three helped while Edward sucked James' venom out of Bella's blood carlisile couldn't get him to stop until the 3rd time , he couldn't stop because when they aste human blood its almost impossible to stop its like a magnet to them , edward hadnt tasted humans blood in a long time as he instead ate animals this is like a vegetarian to humans can live on tofu but never quit satisfied . when edward sucked up to much blood she had a flash back she then woke up in hospital they covered it up by saying she fell down to flights of stairs and went through a window.

Um, I have a question (and I know I should have posted it), but how did they kill him without actually killing the real person?