Leaks by former National Security Agency contractor Edward Snowden have provided new insight into how the government monitors domestic and foreign communications for threats to national security.

Although the government has disclosed some additional details about the programs in response to the leaks, important questions remain about the nature and scope of the surveillance programs.

Without that additional information, it is impossible to know the extent to which the government is peering into the lives of Americans in the name of national security, according to privacy advocates.