BOZEMAN, Mont.—A man reported that someone got into his unlocked car and turned the lights on, draining the battery; a woman had questions about a man who wanted to trade a gun for a puppy; a caller wanted to know how to get his mother to stop harassing him.

In this mountain town (pop. 39,000), police officers' duties extend beyond the daily rounds and reports. They provide fodder for one of the hottest books in town, "We Don't Make This Stuff Up: The Very Best of the Bozeman Daily Chronicle Police Reports."

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