1.30pm - Saturday July 6 Perth Cultural Centre, Northbridge.
Speakers include Greens Senator for Western Australia Scott Ludlam and Electronic Frontiers Australia chair David Cake.
Edward Snowden blew the whistle on an American surveillance program monitoring communications around the world - spying on users of companies including Google, Microsoft, Facebook and Apple.
On June 13 Fairfax reports confirmed Australian intelligence agencies receive what Defence intelligence officials describe as ''huge volumes'' of ''immensely valuable'' information derived from PRISM and other US signals intelligence collection programs.
The Australian Government has entertained the notion of its own PRISM - a mandatory data retention scheme that collects all communications data and retains it for two years.
Mass surveillance doesn't just violate the privacy of law-abiding citizens - it stifles dissent, intimidates whistle-blowers, and exposes journalists' sources: It is dangerous for democracy and does nothing to enhance security.