Adding tags to custom theme

I’ve taken over a site for an organization that is using the following code in the footer of index.php:

<?php the_tags( ‘<p>Tags: ‘, ‘, ‘, ‘</p>’); ?>

However, this isn’t displaying anything. I’ve got categories and comments to display but tags don’t want to show up. I checked the CSS to make sure that it wasn’t hidden for some reason but it’s not, it’s just not displaying anything.

This is pretty standard stuff per the codex, so any ideas as to why it wouldn’t display? Thanks!