Ratley graduated from the University of Texas at Dallas with a bachelors degree in business administration. In 1971, when he joined the Dallas Police Department, he was assigned to several divisions, including vice, child abuse and internal affairs.

He recalls being the only one of about 2,300 fellow officers "who had any kind of degree in accounting," he says. So, "kicking and screaming," he found himself assigned to investigations that involved accounting. "Homicides are a lot more fun," he says. "Fraud was just paper crap."

Since then, though, Ratley has made a career out of it, coming to recognize and delineate the red flags that help investigators detect business fraud. The most glaring? "Good news" in a bad economy, "when bad news is expected," he says. "When business is booming, the problem is that nobody questions good news."

Other red flags are more specific.