The officials would include the prime minister's national security adviser, federal lawyers who work on terrorism cases and intelligence analysts in the Privy Council Office.
The Harper government wants to pull the cloak of eternal secrecy over past and present employees of nine federal agencies and those who used to toil at two now-defunct branches.
They would join the more than 12,000 current and former federal intelligence officials already covered by Security of Information Act provisions forcing them to take the secrets of their most closely held work to the grave.
Democracy Watch, a group that advocates a more open and accountable federal government, calls the latest blanket proposal "dangerously undemocratic."
The Security of Information Act was quickly passed as part of a package of anti-terrorism measures following the Sept. 11, 2001, terrorist attacks on the United States.
The law forbids discussion of "special operational information" including past and current confidential sources, targets of intelligence operations, names of spies, military attack plans, and encryption or other means of protecting information.
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