These days there are at least 30 million security cameras in use on just about every corner around the country.
Now, computer scientists have developed a way to let law enforcement tap into any one of them that isn't protected by a password.
"It's a way to help people take advantage of information that's out there," David Ebert, an electrical and computer engineer at Purdue University, told Wired.
Wired reports that the system is still just in the "proof of concept" stage.
But privacy advocates worry that necessary surveillance could turn into overreach by the government – or even unauthorized use of the system, along with the possibility that someone could hack into it.
"It does open up the potential for some unseemly surveillance," said Dave Maass, an investigative researcher with digital rights group EFF.
*Click here to find out more about this system and what privacy advocates are saying about it.