HARTFORD, Conn. (AP) - Police departments are keeping the data from millions of license plate scans that show when and where Connecticut drivers have been — a practice that is raising privacy concerns.
The Capital Region Chiefs of Police Association, a group of 10 towns, has compiled a database of more than 3.1 million scans, including 2.1 million license plates that were read in 2011 by machines placed on the backs of patrol cars.
Police use the scans to find vehicles that have expired or stolen registration tags or are linked to criminal activity.
But the database also can be accessed by the public and can be searched to show where and when a car has been scanned.
The American Civil Liberties Union obtained the database through a Freedom of Information request and provided a copy to The Associated Press. It's proposing legislation that would allow police to keep the data for two weeks only and would restrict the use of readers to law enforcement.
"Once that data is shared, the police department loses all control of the data," said David McGuire, an attorney for the ACLU of Connecticut. "You could figure out where someone works or when they leave for work. You could use the person's travel to deduce whether they are a churchgoer or attend a political rally or an AA meeting."
A similar regional database is being set up by about 15 departments in southwestern Connecticut, said Redding police Chief Douglas Fuchs, the president of the Connecticut Police Chief's association.
It typically costs $8,000 to $18,000 to set up a patrol car with a reader, Fuchs said. The device then automatically scans any license plate in its view and compares the plates to those on a predetermined list, using information supplied by the National Crime Information Center and the state Department of Motor Vehicles, looking for a match.
"If you have never stolen a car, if your registration is up-to-date, the license plate reader will never know you exist because it's comparing you to a database you are not in," Fuchs said. "This is an invaluable tool for us."
License plate readers have been available for years, but their use only recently has become widespread, in part because the technology has improved, the costs have come down and federal grant money has been made available for departments to purchase the units, Fuchs said.
They also have become the only means for checking the validity of license plates in Connecticut, which no longer uses stickers to show when a registration must be renewed, he said.
The readers consist of a 365-degree camera and a similar infrared camera, connected to character-recognition software that reads license plates. Most departments keep the units operating whenever a patrol car is turned on, scanning every car the officer comes in contact with at speeds of up to 80 mph.
Newington police Chief Richard Mulhall, who helped set up the system for the 10 towns in the Capital Region Chiefs of Police Association, said it began operating at the end of summer 2010 and its use has been expanding ever since. The participating departments made 839 motor vehicle arrests and 28 criminal arrests in 2011 using the technology, he said.
"There was a case when an officer was responding to a fight and fire," he said. "Our suspect said he wasn't at the scene. One of our officers responding to the scene said, 'Let me check the file,' and, sure enough, his plate was scanned in relatively close to the house where this occurred. Eventually, that person admitted to an arson at the house."
David McGuire of the ACLU said they are more worried about others misusing the technology. Some auto repossession companies have already begun purchasing scanners to use in their businesses, he said. It could be used by divorce lawyers, politicians looking to dig up dirt on opponents and even tabloid journalists, he said.
Some states have placed regulations on the scanners. New Hampshire passed a law in 2007 that bans the use of any surveillance technologies on a public way. Maine has a law that restricts the use of readers to the Department of Transportation and law enforcement and requires the data be destroyed after 21 days.
State Rep. Gary Holder-Winfield, D-New Haven and a vice chairman of the legislature's Judiciary Committee said he isn't sure whether lawmakers will act on the ACLU's proposal during this year's session.
"They say technology is expanding at exponential rates," he said. "Legislatures don't move at exponential rates, so technology is outpacing us. It's difficult for us to keep up. But if we focus on balancing the rights of privacy and security, I think at least we'll be focused on the right things."
Fuchs said he would oppose time limits on storing the information. If police develop a suspect in a string of crimes, the data could be used to help link that person to the locations and times where past crimes occurred, he said.
"Suppose we found a pickup truck with a missing child alive inside, and we have four or five other missing