Steps to reproduce the issue

I made some Tag and tagged them on articles or whatever supported items.
Then I unpublished the tag. The tag now disappear from the Tags module. It is fine.

Also, tags set access levels to higher, e.g. Managers, are accessible to non-logged in users.
It appears that tags respect Publish and Access Level only in showing or hiding of tags on the Tags modules, but not the underlying listing logic.

Expected result

It should show a tag-not-found (or permission denied) error.

Actual result

The items tagged with the UNpublished tag (or not permitted as per Access Level) listing still accessible at http://mysite/component/tags/tag/2

System information (as much as possible)

PHP 5.4.16
Webserver Apache/2.4.6 (CentOS) OpenSSL/1.0.1e-fips PHP/5.4.16
Joomla! 3.6.5 Stable [ Noether ] 1-December-2016 22:46 GMT
Joomla Platform 13.1.0 Stable [ Curiosity ] 24-Apr-2013 00:00 GMT

Additional comments