Do NPCs use the same perk trees as player characters?

Solution 1:

I saw Karliah perform a Silent Roll which is Sneak 100. You may want to look at http://www.uesp.net/wiki/Skyrim:Classes for more information.

Solution 2:

Absolutely. Mages dualcast, tanks are stagger resistant (even against my spells, grr) archers move faster with the bow drawn. I've seen all of these perks used by higher level enemy npcs. It's nuts.

Solution 3:

You don't need perks to dual cast or to resist stagger attacks. NPCs don't have perks. The "silent roll" is a glitch because a follower will mimic your movements. If you walk, they walk, if you run, they run, if you sneak, they sneak, and if you forward roll they forward roll.