I was watching the Star Trek: Deep Space 9 episode, "Dax", wherein a hearing is conducted about whether Jadzia Dax should be extradited for murder and treason committed by Curzon Dax.
I know it's termed an "informal hearing", but it appears to boil down to whether Jadzia Dax can be held responsible for Curzon Dax's crimes, and a philosophical debate is held where they discuss that Jadzia has the memories and can even feel some of the guilt, and while medically they are different people (even down to different brainwave patterns) it's not quite as clear whether the Dax component is a different person, etc. A "Trill expert" (in that he is a Trill) is even brought in to talk about the emotional feelings involved.
However, what is never discussed for some reason, is the legal position on the Trill homeworld. Surely whichever side it favoured should have called a legal expert to tell them the answer - while the opposition may have rejected this, considering it out of their jurisdiction, it would have gone a long way to convincing the arbiter. (Intaro appeared to be touching this before he was interrupted his mother who rendered the whole question moot anyway)
So the question is, are there laws on the Trill books which indicate whether culpability for crimes pass from host to host? It would seem the obvious thing that they'd need to come up with when joinery was first discovered / invented.