diff --git a/phpBB/includes/functions_display.php b/phpBB/includes/functions_display.php
index 628bb8e9f5..ad6a64f897 100644
--- a/phpBB/includes/functions_display.php
+++ b/phpBB/includes/functions_display.php
@@ -538,6 +538,12 @@ function get_moderators(&$forum_moderators, $forum_id = false)
 		return;
 	}
 
+	// If we don't have a forum then we can't have a moderator
+	if (!sizeof($forum_id))
+	{
+		return;
+	}
+
 	if ($forum_id !== false && is_array($forum_id))
 	{
 		$forum_sql = 'AND forum_id IN (' . implode(', ', $forum_id) . ')';