a related note. If a Muslim slaughters an animal in a non islamic way (like chop the head off or recite a shirkiya kalima or kill the animal by an electric shock) then the meat is no longer halal … just like that, ahl-e-kitab need to follow the protocols set by their own religion (and those protocols are similar to ours). If they deviate from those protocols then the animal slaughtered by them is no longer halal.