Dzhokhar Tsarnaev was charged with conspiring to use a weapon of mass destruction in his hospital room Monday afternoon.

The surviving suspect in the Boston marathon bombing was captured Friday, just one day after the FBI released video images of the Tsarnaev brothers to the public.

The role of cameras in the case sparked a debate weighing privacy against public safety.

Cameras played a critical role in piecing together what happened in Boston exactly one week ago.

Investigators poured over photos and videos from onlookers and surveillance footage before ultimately releasing images of the two suspects. When the FBI first released the images, special agent in charge Richard DesLauriers emphasized the public’s important role in this investigation and others like it.

“For more than 100 years, the FBI has relied upon the public to be its eyes and ears. With the media’s help, in an instant, these images will be delivered directly into the hands of millions around the world,” DesLauriers explained.

Meanwhile, in Chicago, Mayor Rahm Emanuel said last week the city continues to add cameras for security reasons.

The ACLU reported that Chicago already has the largest urban network of public and private surveillance cameras—more than 10,000.

“They [cameras] serve an important function, for the city in providing the type of safety, on a day-to-day basis, not just for big events like a marathon but day-to-day,” Emanuel noted last week.

But while the mayor was quick to tout the upside of surveillance, others were just as fast to voice their concerns. And not just as it relates to privacy.

Sharon Franklin is senior counsel for the Constitution Project, a D.C.-based watchdog group.

“It’s important to note the role of surveillance here was not helpful in preventing this attack. The role of the  surveillance footage was in identifying the suspects after the event and in helping to track that down,” Franklin said.

The project developed guidelines for cities installing video surveillance systems.

Among the suggestions —that tape not relevant to the criminal investigations be purged.

Franklin said she doesn’t want the government building a database of innocent people who happen to be present at the scene of a crime.

“In this case, we don’t want them starting criminal or terrorist files on all sorts of people who were simply innocently watching the marathon,” Franklin explained.

Katie O’Brien is a WBEZ reporter and producer. Follow her @katieobez.