The American Civil Liberties Union has expressed profound privacy concerns about the proliferation of CCTV cameras. But in an age when people routinely snap photos and videos on their smartphones and upload them to the Web, it is tougher to argue that people assume they won’t be monitored in public.

While the current system may be sufficient for after-the-fact investigations, Boston lags New York, London, and other cities that make maximum use of closed-circuit television cameras for crime prevention.

Good camera work played a key role in the identification of the suspects in Monday’s bombings. But the reliance on store-mounted cameras and cellphone video from the public suggests that Boston Police could benefit from updating their approach to surveillance cameras — particularly by placing cameras more systematically at sporting events and other locations where large numbers of people gather. This step alone may have some deterrent effect.

Neither Boston Police nor city officials could say Friday how many government surveillance cameras are now used in public spaces. The ACLU determined that there were at least 55 CCTV cameras in use by Boston law enforcement in 2007 in addition to many private systems. Since then, Boston has used Homeland Security grants to purchase more cameras and placed them under bridges and in shopping districts. But it is safe to say that New York City, with about 3,000 security cameras in Lower Manhattan alone, makes Boston look like a remote desert when it comes to surveillance.


Given the horrors at the Marathon finish, Boston officials should be keeping close tabs on new surveillance software that puts emphasis on prevention as well as detection. New systems have been designed to alert officials of unusual behavior. Such a program, for example, might have flagged the Marathon terrorists when they set down their packs and walked away.

High-powered surveillance cameras may make people a little nervous. But rudimentary bombs like those used to kill and maim spectators at the Marathon fill people with terror. It’s worth remembering, too, that the first and best instinct of law enforcement was to share the images with the public and ask for its help.