Some of the security related system/kernel tables in AX 2012, like for example SecurityRole, is backed by Views in the model store.
If you look at the Views in the model store you can see that some fields hold a label id rather than a text. For SecurityRole, the fields Name and Description holds label ids.
Somewhere in the AX kernel these label ids are converted to actual texts according to the language of the user. So inside AX we don't see these labels, but we see the language specific texts.
This is also the case if you create a View where these tables are part of the meta data.
However if you change the language for your user, it doesn't seem like these Views are updated according to the new language. They keep returning data in the previous language, even after restarting the client and AOS. The only way I have found to make it use the new language is to manually synchronize the view from the AOT.