@Vincenzo -- Things are even more complex than that. Quite often, a state attorney general will release an opinion declaring that something about a ballot initiative is improper.
Citizens might still try to get it on the ballot, but once the attorney general finds some deficient the chances are good that it will be struck down by the courts.
There are some that claim that the fact the judicial system exercises such power over these initiatives is somehow wrong. But it is important to recognize that courts exist to protect the laws and rights of citizens. Anything that violates those laws or rights should be struck down.