What is the role of research in liberal arts college faculty evaluation? Lately, I've been wondering why institutions with a primary emphasis on undergraduate education (e.g. liberal arts colleges) value research output amongst their faculty. This is not intended to dismiss the research of LAC faculty, but rather to delineate what value the institution/department gains by hiring candidates with superior research output, perhaps at the expense of someone with a stronger teaching record. Here are several reasons I have heard, arranged in reverse order (approximately) of direct student benefit:


Current faculty wish to promote research in the discipline for its own sake, without regard educational benefits for the students
Tradition, or emulation of more prestigious institutions.
Faculty need a strong enough research output to get tenure (a somewhat circular reason)
Reputation within the research community enhances departmental and institutional prestige, with incumbent benefits for students. 
The faculty can extend their academic network to their students. Examples of this might include increased regard for letters of recommendation and awareness of (non-)academic opportunities.
Research output is a proxy for breadth of knowledge within the discipline, hence for value of content in instruction, both formal (course syllabi) and informal (answering that random question during office hours).
Research output corresponds to the baseline knowledge needed to supervise undergraduate research and teach best practices.
Research activity is the best way to keep faculty aware of changing trends in the field, which in turn gets incorporated into educational practices. After all, academic careers last a long time.


I'm sure there are many valid reasons missing from this list, including some of the most important. I would like to know from a institutional/hiring perspective:

a) What reasons for valuing research activity are missing from this list?

b) What benefits are weighted most heavily? Which are given little or no thought?

c) To what extent are these benefits distinct from the ways that research profiles are evaluated by hiring committees?
I believe your list implicitly says this, but I'll include an answer anyhow, because I think this is an excellent question and I am interested in hearing answers that supplement what I write below.

Teaching divorced from serious engagement with the subject matter taught is arguably a very suspicious activity. In principle, if someone is paying a large sum of money to be taught a subject, the teacher should not only be able to convey his subject clearly, but also should be a practitioner of that subject. The living content of a subject is found in the minds of its practitioners, and so attempts to teach even the ideas which are archaic without the living insight driving honest contemporary investigation of the topic is very much in danger of becoming stilted, sterile or, perhaps worst of all, too packaged or neat.

One might oppose this view by pointing out that most undergraduate students do not need to know what is going on at the front lines of any subject, and the historical efforts and ideas, presented clearly in an engaged way, are enough. For cultural purposes, this may be so. However, a passion for teaching at the highest level morally ought to be accompanied by a passion for learning at that level, which is what research or serious scholarly engagement is at its heart.

Another strong argument against requiring research is the following: students at an average primarily undergraduate institution are generally not going to be prepared for graduate study in certain fields, so why should time and energy of faculty be sunk into research in such fields. (Many good institutions with PhD programs also need to remediate entering PhD students, suggesting that this problem stretches beyond undergrad-only institutions.) Again, though, I answer that learning and teaching should, ideally, not be decoupled.

A third argument is that it is possible for an engaged teaching faculty member to learn for his own enrichment and that this does not need to happen at the level required for research or peer review. I can only answer this, unfortunately, by my personal experience and opinion. It bothers me that when a student enters university in order to learn a subject, he cannot tell the quality of knowledge he will receive (whether the community of peers of a student's professor regards the professor's ideas and approaches as relevant). It is our responsibility to ensure that students are exposed, to the best of our ability, to ideas that have impact. I cannot see how to do this without being able to point to peer-reviewed faculty contributions.