I really hate giving the answer "that depends" to reference questions. Sometimes, though, that's the answer. At least, the first answer. The reference interview can usually give you more details on the real question, so explaining WHY "that depends" is crucial.
A woman called the reference desk with the question "What do republican corporations pay in taxes?" I wondered if she meant the republican party itself. No...she had an argument with her sister about how corporations get a lot of tax breaks and don't really pay much in taxes. Her sister believes that corporations pay a lot in taxes. Who's right?
The next part of the reference interview was my asking how republicans fit into the equation. She conceded that they didn't. At this point, the question turned into "What do corporations pay in taxes?" You see how "that depends" came into play.
We chatted a bit about tax credits and different types of corporations (ie. a small business is not going to pay the same taxes as, say, Ford Motor Company). I pointed her to http://www.irs.gov/businesses/corporations to read all about it. I suggested that sometimes a company's annual report includes financials that includes taxes they paid that year. There are some basic flat-rate percentages that could apply in certain circumstances, but there isn't really a one-size-fits-all answer for how much ALL corporations pay in taxes. All PEOPLE don't pay the same taxes, so why would all corporations? The patron was not happy with my answer or with the reasons I offered for why "that depends." Even after we talked about it, she said she guessed she would have to go online herself and get the dollar amount that republican corporations pay in taxes. I suggested she ask a tax preparer what they thought, or call the IRS hotline.
This is just one example. How about a scenario where the patron has a very personal or private situation, and doesn't want to give you more information to help find an answer. I'm thinking of medical or financial questions. I mean, "Where is the medical section" and "Where is the legal section" are asked quite a lot, and it takes some subtlety to get more information from the patron to narrow their search. The reference librarian in me just doesn't feel right saying "these three rows" and leaving them to figure it out. The human in me does not want to pry or embarass the patron. I also don't want to make the patron feel stupid or wrong for asking. I often ask something like, "What area of law are you interested in?" or just point out "This section is about family law, further down this row is about tax law, and the other side goes into consumer law. Does that help?"
What are your strategies for answering those "that depends" questions?(Especially when there truly is not one answer and the patron just won't accept that!)