I have worked for both University and non-University Museums and served on
exhibitions committees for both.  Usually they are set up so that they
serve in a advisory capacity, with final decision being made by the staff
( and with plenty of staff on the committee!)  A couple of things that
might be useful:
1.  Staff can screen exhibitions before the group looks at them, therefore
making some preliminary decisions.
2.  Staff can set up an exhibitions rotation schedule that can guide the
committee quite strongly.

What this type of committee does, is allow the museum to hear multiple
voices.  As well as including members of the board, there are often at
large members who represent various segments of the community.  I feel
that an exhibitions committee is quite important - we are here to serve
the community who enables is to be tax exempt!  In addition, it alleviates
some to the complaints of elitism art museum often encounter and may help
to win you new audiences.

Kathrine Schlageck
Beach Museum of Art