CHARLOTTE, N.C. — Three letters and four numbers on a license plate give away more information than you might think.
This information is gathered from license plate readers across the Charlotte area and stored for weeks -- helping police to solve crimes, tracking you from home, to work, or to church.
Officials said license plate readers are strategically placed all over the city and when a wanted car is identified, the Real Time Crime Center gets a signal. It flashes red and tells investigators where the car is.
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Charlotte-Mecklenburg police Lt. Travis Pardue heads the Real Time Crime Center. He said the technology is one of the biggest weapons in fighting crime.
"We employ this technology in places that enhance community safety," Pardue said. "We're looking for missing persons, fugitives, stolen tags, stolen cars."
Mike Meno and the American Civil Liberties Union said they have some major privacy concerns with readers and the fact they cast a wide net scanning the tags of everyone who drives by.
"We're not comfortable with this sort of unfettered access to our personal data," Meno said. "Regardless, whether we are suspected of a crime, whethere there is any reason for the government to be tracking our location."
Meno said the data from the license plate readers can tell a lot about your personal life.
"Your location can tell a lot about who you are as a person and it can reveal sensitive data that I think most of us would like to keep private," Meno said.
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The system can read 3,000 tags in an hour. If you multiply that by 24, that's 72,000 tags in a day and 26 million tags in a year.
At one time, police agencies could keep the data for as long as they wanted, but in 2015, the legislature changed it limiting it to 90 days.
CMPD said that data is not shared with any third parties and access within the department is limited and monitored.
"The information is purged after 90 days period and without fail," Pardue said. "We can audit what cameras and what systems are being used by who and for what purposes. In addition, there is oversight."
Police don't believe there is a privacy trade off and they said the system has helped to solve hundreds of crimes like the arrests of Davonte Everett and James Allen for a series of convenience store robberies.
Last month, a relative reported Kelly Blake and her three children as missing so her license plate triggered a follow up by an officer.
"He was like 'You know you're considered a missing person' and I was like 'Yeah, I'm OK. I'm not missing or nothing like that,'" Blake said.
There's no evidence police in Charlotte have misused the technology. Other states have seen problems such as data going to third parties like the Repo Man.
Police insist that would never happen in Charlotte and that it is not like putting a tracking device on a car.
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"As good as the system is in the city, it doesn't have the capacity to follow a car continously. It's just not designed that way," Pardue said.
Blake said she doesn't need to be convinced because she saw the good up close and personal.
"If I was truly a missing person, they would have found me quickly," Blake said.