The best way to prevent tomorrow’s crime is to solve the one that happened yesterday— or last week. Boston Police do a good job responding to the constant calls for service in a city of 600,000-plus people. But they need more tools to help them get clues and identity suspects, especially in the wake of violent events.

Last Tuesday evening around 7:30p.m., a Dorchester Ave. convenience store owner was shot in the stomach during an armed robbery. Witnesses, including the victim, were able to help get out a description of the assailant. Within a matter of minutes—after an intense hunt— police from Area C-11 arrested a Roxbury man who was later charged with the crime.

Earlier that same day— around 5 p.m.— police had been called to Lower Mills for another report of a shooting. They found a 30 year-old man suffering from a life-threatening gunshot wound to the head next at the corner of the CVS pharmacy right across from the Boston Public Library branch. It was election night, but despite the heavy foot-traffic in and around the branch, no one was able to give a good description of the suspect or suspects. The victim was so grievously injured that he could not communicate.

Police later pulled surveillance tapes from inside the pharmacy— and a spokesperson for the BPD says that the footage is “now part of the investigation.” But police will not say whether the crime —as it unfolded outside— was captured, but they have not issued any description— or images— of an assailant or assailants.

Boston lacks a robust network of closed-circuit camera coverage in and around our business districts, public parks, library branches and other larger residential complexes. There are no security cameras at the Lower Mills branch, for instance. BPL spokesperson says there are cameras currently in place in Fields Corner, Mattapan, Grove Hall, Codman Square, Dudley and three other branches. Jamaica Plain’s branch will get them next under a planned renovation.

“Our goal is to eventually have cameras at all of our locations citywide,” said BPL spokesperson Gina Perille.

The Walsh administration should push harder to fix this deficiency, especially in neighborhoods in which small businesses don’t have the same level of private security infrastructure that downtown property owners can pass along to assist authorities. Such a network of closed-circuit cameras doesn’t need to be constantly monitored, but it should be fed into a central place — under BPD command— where detectives can easily and quickly access them for review after an incident.

The city also needs to consider recalibrating its own systems to allow for cameras to be installed on public assets without putting the burden of maintaining or monitoring the equipment.

Police, already stretched thin, need help. Human witnesses are critical, but they can also be fallible, unwilling to come forward or limited in their memory and capacity.

Neighbors should rightfully expect that city government make use of the latest technology to enhance our public safety, as is now commonplace in other large cities like New York and London. It needs to become a higher priority here in Boston’s neighborhoods. We hope that as the mayor and his team craft their budget for the coming year they will focus on this as a priority.