You may not see them, but they are watching your car's license plate.
Charlotte-Mecklenburg Police have started installing about two dozen cameras at intersections around the city that are capable of reading and storing every license plate that goes by.
The cameras are paid for with more than $1 million in grant money and are here just in time for the Democratic National Convention.
"Anything that we have out there that we can implement for the DNC, from officers to technology -- well, this is certainly part of that technology that we want to use for it," said Major Johnny Jennings of the Criminal Investigations Division.
Jennings said the camera will be used only for public safety matters and won't discuss exactly how many they will have, but he said they can send information to a server at police headquarters or to a patrol car stationed nearby.
The department has already been using similar cameras in individual patrol cars, but Jennings said the new cameras could effectively turn any patrol car into a tag reader.
But some question how much information the police department should be gathering.
"What is the purpose that you're using it for? That is the real question in these situations," said Jim Gronquist, who is an attorney and a member of the ACLU. He worries that the cameras could be used to gather personal information.
Police say they have heard that concern before and say it should not be an issue.
"We absolutely understand that. The thing that we're using this for is for public safety," Jennings said, adding that data not tied to an investigation is regularly purged from the database.