Moderators able to ban more than usergroup members

[Glock]

I want Moderators to be able to ban everyone who isn't a Administrator or Moderator. From reading another thread I figured out I should replace

if ($bangroup['usergroupid']>6) {

with

if ($banuser['usergroupid']!=6 or $ismod) {
echo "<p>You may not ban someone who is not a normal registered user!</p>";
} else {

My Administrator usergroup is 6, and this code does not work. Just wondering what the proper code is, and what one for allowing Moderators to ban Moderators also is, in case of a compromise of security.