I frequently have disputes with law reviewer editors over the use of hyphens. Unlike co-conspirator Eugene, I'm not a grammatical expert, or even someone who has much of an interest in the subject.
But I do feel strongly that I shouldn't use a hyphen between words that constitute a phrase, as in "hired gun problem", "forensic science system", or "toxic tort litigation." Law review editors seem to want to generally want to change these to "hired-gun problem", "forensic-science system", and "toxic-tort litigation." My view is that "hired" doesn't modify "gun"; rather "hired gun" is a self-contained phrase. The same with "forensic science" and "toxic tort."
If readers want to set me straight, or better yet agree with me, feel free to do so below.