code/model/BlogPost.php
public function canView($member = null) {
		if(!parent::canView($member)) return false;

		if($this->PublishDate) {
			$publishDate = $this->dbObject("PublishDate");
			if($publishDate->InFuture() && !Permission::checkMember($member, "VIEW_DRAFT_CONTENT")) {
				return false;
			}
		}
		return true;
	}
public function canView($member = null) {
		if(!parent::canView($member)) return false;

		if($this->PublishDate) {
			$publishDate = $this->dbObject("PublishDate");
			if($publishDate->InFuture() && !Permission::checkMember($member, "VIEW_DRAFT_CONTENT")) {
				return false;
			}
		}
		return true;
	}
Checks the publish date to see if the blog post has actually been published.

@param $member Member|null

@return boolean