i'd say you're guilty simply for creating the monster at all: mentally ill or not,digging up dead bodies,sowing them together and bringing them to life is a little beyond what most would see as reasonable even for someone that's insane (you didn't HAVE to create the monster for any reason: you CHOSE to and the amount of work required pretty much requires you to be sane enough to know what you're doing).

also you live in,what? the 1900's give or take? your ass can be locked up or even killed for a LOT less so you were already screwed.

you're guilty and will be lucky if you're not hanged.