Reports that area police departments are compiling license plate information into a database has some people questioning whether privacy rights are being threatened.

According to the Associated Press, 10 towns in central Connecticut are participating in a database that shares 3.1 million license plate scans and about 15 departments in southwestern Connecticut are in the process of setting up a database. The scans provide data on whether registration tags are stolen or expired and also if the vehicle is stolen, the AP story said.

However, a lawyer for the American Civil Liberties Union voiced concerns that the database could be used to track where people are going or when they leave for work, according to the AP.

The Darien Police Department doesn't participate in a regional database currently but Capt. Fred Komm said the department is doing some preliminary exploration about possibly sharing data in the future.

"Right now we are exploring a partnership with nearby towns like Stamford or Westport but it is purely exploratory at the moment," Komm said.

The department is equipped with a license plate scanner which is used to check for expired registrations or if the vehicle is stolen. The data is then kept for a year before it is purged from the system, Komm said.

"The scanner hits on stolen cars and expired registrations, but it can also be used at a later date if you have a crime that's been committed somewhere and you need to pull up information about the vehicle that was involved," he said. "We keep the data for a year before we reset and erase everything."

The scanners will also alert officers to vehicles with unpaid parking tickets; information that can be sent to the Department of Public Works which handles parking violations, Komm said.

The debate about how long data should be kept is an issue legislators will need to consider, State Sen. Bob Duff (D-25) said.

"I don't know if there will be legislation this year but the reports are just starting to come out, so this is something we will need to look at and think about," Duff said. "This isn't something we should have a knee-jerk reaction to."

One area that raises some concerns for Duff is how long the departments keep the data and who has access to the data. He said he was concerned with the idea of law abiding citizens being able to be tracked through the database.

"It becomes kind of a big brother thing. There have to be parameters around how the data is used and who is accessing it," Duff said.

According to the AP, the ACLU wants to propose legislation which would require departments to purge all license plate scan data after two weeks and the scanners would only be used by law enforcement.

"As a tool I think the license plate scanners are very useful," Duff said. "I spoke with officers in Norwalk and they said the number of illegal license plates being used has dropped to almost zero because people know the police cruisers are equipped with the scanners."

State Rep. Terrie Wood (R-141) said she was unsure why police departments needed the database and what purpose the database served.

"It doesn't make sense because the police already have the capability to check for stolen cars," she said.

Wood was also concerned the database was crossing privacy lines and becoming too intrusive.

"I don't see a need for the database. It seems like big brother is watching," Wood said.

Duff noted the state's decision to stop issuing registration stickers for display on license plates saved the state about $250,000 and also prevented thieves in the cities from being able to break off the corners of plates with the stickers to use on other vehicles.

Any decision to participate in a regional database is still up in the air as the department considers the benefits and costs of participation, Komm said.

The Associated Press contributed to this story.;; 203-972-4407