In instructor training, we're taught to have the new archers shrug their shoulders as an example of what we don't want them to do when they draw the bow. Every good archer I've ever observed shoots with their shoulders down. If you're a fairly new shooter still trying to develop form, I would recommend shooting with your shoulders down, perpendicular to the target, and your head turned as much as possible to face the target, not resting your chin on anything, since that's what has proven to be successful for most other people.