The entire original SW trilogy is rated U (the lowest classification possible for large films) by the BBFC as is Episode I. Just off the top of my head these movies contain tons of laser fights, dead bodies, burning corpses, slavery, numerous counts of choking, torture by electricity, several lost limbs, a character being completely cut in two, and large scale warfare in every movie.

I can understand the films getting a PG due to the fantasy nature, but I struggle to see how all of the first four obtained a U when films such as Toy Story, Big Hero 6 and Kung Fu Panda fail to achieve it.

Can anyone explain this to me? It's hard not to suspect a degree of bias considering all four films.