caught in the act. Almost two dozen states use traffic cameras to catch drivers speeding and running red lights. Big tickets, big fines. Well, tonight, surprising, new questions about how often those... See More
caught in the act. Almost two dozen states use traffic cameras to catch drivers speeding and running red lights. Big tickets, big fines. Well, tonight, surprising, new questions about how often those cameras are wrong. One city's launched an investigation because of so many mistakes. And ABC's senior national correspondent, Jim Avila, shows you what you can do. Reporter: It's the flash out of nowhere, when you don't expect it. Sometimes when you don't deserve it. A Baltimore intersection. This driver has clearly stopped. But the unmanned speed camera cites this car, brake lights on and traffic whizzing in front of it, for going 38 miles per hour in a 25-mile-per-hour zone. A costly mistake at 40 bucks a ticket. Among the documented 10% error rate for speed cameras in Baltimore. Some individual cameras off by as much as 50%, according to an audit leaked to "The Baltimore sun" that has the city council investigating. Nationwide, about half the states use cameras. Cheaper and easier than radar guns. But class-action suits in Ohio and New York attack their reliability. Los Angeles stopped issuing camera tickets altogether. This Maryland driver videotaped his speed, ten miles below the limit. The speed camera ticketed him for ten miles over. The car with the speed camera was right here. Reporter: Schoolteacher Erin Grunden got five tickets leaving her Maryland school. I was clocked at 51 miles per hour, which a math teacher figured out is physically impossible for me to be going that fast. Reporter: Her 10-year-old Honda couldn't reach that speed in the short distance from the school driveway to the ticket camera. In all, 22 teachers were ticketed here. If you give companies an incentive to ticket more, lo and behold, they will ticket more. Reporter: California has banned per ticket fees. But advocates say cameras slow people down. Some cities are using cameras in new and different ways. This one is monitoring a stop sign, not a stoplight. If you roll through the stop, it will click. Costing you cash, in a flash. Even when the picture doesn't tell the story. Jim Avila, ABC news, Washington.
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