This is one of those questions where any answer could be correct. I'm assume that the PokeWorld will enforce standard laws like we have in the real world but for the PokeWorld I guess you can just slot in Pokemon to real world laws.
No stealing would apply to the PokeWorld but it would also apply to using your Pokemon to steal. Abuse is another one. In the real world animal and human abuse is illegal some the abuse of Pokemon will also be illegal in the PokeWorld.
So in short, yes the PokeWorld will have laws of it's own but as it is not a massive deal in a kids TV show / Game then Nintendo haven't bothered writing out an entire list of rules and regulations for the Pokeworld. But we can assume that standard real life rules and laws would apply in the PokeWorld and would incorporate Pokemon within them.
Although I don't think Capital punishment would ever be considered in the anime or games o.O