The role street cameras played in catching the alleged Boston Marathon bombers is stoking debate about how much more, or less, privacy should be sacrificed for security against terrorists.

Almost 12 years after the national trauma of the original Sept. 11 attacks, a televised act of terrorism followed by the swift killing and capture of the two suspected perpetrators has opened questions about what is acceptable to a public already chafing under intrusive security measures unheard of until this century.

{mosads}Some lawmakers argue that there can be no expectation of privacy in public, and that additional surveillance cameras are the best way to prevent attacks or track-down home-grown terrorists who operate off the grid of traditional communications monitored closely by U.S. intelligence authorities.

“If you walk down the street, anyone can look at you, anyone can see where you’re going. You have no expectation of privacy when you’re out in public,” said Rep. Peter King (R-N.Y.), the former chairman of the Homeland Security panel and a member of the Intelligence Committee.

“This is not looking into someone’s home or doing something that would require a search warrant,” King said in an interview with The Hill. “We’re talking about something which is out in the open.”

Other lawmakers agree public cameras can be useful in the war on terrorism, especially in urban environments where terrorists can easily slip into the crowd.

But they argue you cannot put a camera on every corner of small-town America — nor should government want to. People will not accept that level of surveillance, they say.

The debate about cameras is one part of a broader discussion about how to strike the right balance between security and civil liberties. The issue incorporates everything from the effectiveness of airport security checks to the appropriate powers of surveillance that the government should have over private citizens’ communications.

“I think in the larger cities [more cameras would be good], to the extent that people are willing to accept [them],” said Rep. Mike McCaul (R-Texas), the chairman of the House Homeland Security Committee. “In smaller towns, you’re going to have people who have privacy issues and they don’t want cameras. But in New York it’s pretty effective, and in larger cities.”

Camera footage was essential in helping authorities identify bombing suspects Tamerlan Tsarnaev, who was killed in the early hours of Friday, and Dzhokhar Tsarnaev, who was caught that evening, after a massive manhunt that effectively shut down the city of Boston.

The two allegedly killed three people and injured approximately 180 by placing home-made bombs near the finish line of the marathon. Their attack caught intelligence agencies off-guard. The two were not known terrorists, although the FBI had interviewed Tamerlan in 2011 at the request of a foreign government believed to be Russia. Federal authorities asked for the public’s help in apprehending them by highlighting pictures taken of the two near the marathon.

Those images — shown in photographs and video — were plastered on every television and website within seconds of the FBI releasing them. 

The number of images snapped of the two suspects reflects deep changes in American society since the Sept. 11, 2001, attacks.

Cameras capturing the public’s every move have become much more common and are used for everything from protecting homeland security to ticketing traffic violations such as speeding.

The electronics market research group, IMS Research, estimated that 30 million surveillance cameras have been sold in the United States in the decade after 9/11, including to private homes and businesses.

Following the 9/11 attacks, New York City constructed the most expansive camera network — known as the “Ring of Steel” — in the United States. It consists of more than 3,000 cameras in lower Manhattan. An additional 4,000 cameras monitor the city’s subway system.

The network is creeping into Midtown Manhattan as well and lawmakers are eyeing it as a possible template for other cities.

Boston is much smaller than New York City and, as a result, has fewer cameras in place. According to the American Civil Liberties Union (ACLU), there are about 60 law enforcement cameras in addition to the roughly 600 cameras that monitor the city’s subway and area metro system.

Foreign cities have instituted much more of a Big Brother approach.

After the attempted bombing of Times Square in 2010, New York City Mayor Michael Bloomberg looked to London, which is one of the most heavily-monitored cities in the world. Since the 2005 bombings rocked the British city, killing 52 people including the attackers, London has installed more than 12,000 security cameras.

Some lawmakers are worried all of this surveillance will come at a cost to freedom.

“I look at Boston, and I think what could we possibly have done and what could you put in place now that would still allow the freedoms that we’re used to in this country?” said Sen. James Inhofe (R-Okla.).

“If you micromanage these things, if you try to figure out something you can do through government to stop every possible thing in a free country from happening, I don’t see that it’s possible,” Inhofe continued. “It sounds good, it’s a politically popular thing to say, but I don’t think you can do it.”

Michael German, a senior policy counsel for the ACLU and former FBI special agent, said the group sees the benefit, especially in heavily populated urban settings, to having street cameras. But officials need to consider, he said, that cameras have not proven to deter acts of violent crime, are very expensive to put into place and could open the doors for government intrusion into private life.

“There are appropriate uses for security cameras at large public events or at government buildings that are known targets,” German said.

“What we don’t want to happen is for millions of innocent Americans to have to be surveilled constantly anytime they go out in public and for the government to maintain databases of those public movements. That doesn’t necessarily improve security.”

 Sen. Mary Landrieu (D-La.), who heads the upper chamber’s Appropriations subcommittee overseeing and funding homeland security, said she thinks the country is already under a great deal of government and private surveillance.

“Maybe we could have more cameras. I would have a hard time believing there’s another space to put one. Maybe there is, but we have cameras everywhere, it seems to me,” said Landrieu.

“If there’s a cost effective way for us to identify every backpack that’s laid down on ever sidewalk every day of the year, I’m open to talk about it. But it’s not for lack of trying or vigilance. It’s just the nature of what this is. And so we’ll see. I don’t think we want to overreact.”