The California Supreme Court on Wednesday blocked a proposal that would split the state into three from the November ballot. The court wrote that it took the step “because significant questions have been raised regarding the proposition’s validity and because we conclude that the potential harm in permitting the measure to remain on the ballot outweighs the potential harm in delaying the proposition to a future election.” Last week, an environmental group sued to have the measure removed from the ballot. To substantially alter the state's governance under the California constitution, the group argued, a constitutional convention would need to...