someone who has absolutely nothing to lose. batshit crazy people are different from regular crazy people because of their attitude and activities. a regular crazy person would shoot at a plane with a pistol. a batshit crazy person will jump off of one plane with a knife in their hands, onto another, break the glass and kill the pilot ... and land safely. in order to be truly batshit crazy the person must do the most outrageous things every and still return safely.
crazy: throw a brick through your window
batshit crazy: throw a brick through your window, call the cops, wait for them to arrive, tell them what they did, and still get away.