This code will retrieve the user id of the logged in user. It will then check to see if the user has the Cms Administrator role. I used this logic with a custom field so I could control the ability to edit.
#set ($foundUser = $cmsuser.getUserByUserId($session.getAttribute("USER_ID")))
#if($foundUser)
#if($cmsuser.isUserRole($foundUser, "CMS Administrator"))
yes
#end
#end