PRINCEVILLE, Hawaii—In his work, travel writer Andrew Doughty often deals with mosquito-infested rain forest and treacherous riptides. Recently, he had to grapple with a new career challenge: a proposed state law that would hold Hawaii guidebook writers personally liable for deaths or accidents at spots they recommend.

Mr. Doughty, a longtime Hawaii travel writer, didn't take the plan seriously at first. But he had reason to worry about its implications. As the author of "The Ultimate Kauai Guidebook: Kauai Revealed," Mr....