Law enforcement agencies in Massachusetts regularly use a database of millions of license photographs to track down the identities of suspects, according to a new Boston Globe report.

The program is similar to efforts in at least 26 other states, which allow police to use facial recognition software to scan license photos as they chase leads in criminal investigations.

The Globe reports that while the state RMV has had access to facial recognition technology since 2006, it was originally pitched as a way to prevent people from obtaining fraudulent licenses, and that its role as a criminal investigation tool is not widely known.

Last year, federal, state and local law enforcement agencies gained access to 331 license photos, which turned up matches for 101 possible suspects, according to statistics obtained by the Globe.

The report on the program opens another front in the ongoing push-and-pull between police in Massachusetts and privacy advocates.

State authorities will be able to search for "hotlisted" vehicles scanned by the new all-electronic tolling system on the Massachusetts Turnpike during public safety emergencies.

And the American Civil Liberties Union of Massachusetts has slammed the Boston Police Department's planned implementation of social media scanning software, which would give the department a drastically increased ability to monitor and analyze public internet posts. The department has said the information searched is already public, and that the software is a useful public safety tool.

The ACLU is similarly unenthused with the license photo program, according to the Globe report.

"When you go to the DMV to get your license, you do not expect your photo to be part of what has essentially become a law enforcement database used for criminal investigations," Kade Crockford of ACLU of Massachusetts told the Globe.

David Procopio, a state police spokesman, defended the use of facial recognition as valuable and subject to privacy safeguards.

"Facial recognition is a valuable tool for identifying suspects, and one that we use with appropriate discretion," Procopio told the Globe. "It can help solve serious crimes, and bring justice to victims, and prevent further crimes from being committed."