Civil libertarians have criticised the ACT government's use of laws enacted eight years ago for the Sydney Olympics to bolster police powers for next week's Beijing torch relay in Canberra.

Police have been given increased powers to prevent violent clashes between pro-China and pro-Tibet demonstrators during the only Australian leg of the Beijing torch relay on April 24.

The special powers will allow Australian Federal Police officers to search protesters along the relay route and ban them from carrying "prohibited items" which could be used as weapons, including balls, eggs, balloons filled with paint and buckets of water.

But the NSW Council for Civil Liberties says the move is dangerous.

"What we often see is that they say powers like this are needed for extraordinary circumstances but then often it will be used later to argue that the powers should be permanent," the council's president, Cameron Murphy, said.

"Then the powers become something that is put into every day use and become the new norm."

The increased police powers have been declared under the Major Events Security Act 2000, which was enacted in the lead-up to the Sydney Olympics.

The declaration covers the 20km relay route from the southern shore of Lake Burley Griffin to Parliament House and along Commonwealth Avenue to Canberra's main business precinct, Civic.

"It's unacceptable that powers like that are remaining on the statute books when the original reason for them being used is well and truly gone," Mr Murphy said.

The special powers limited people's fundamental rights to protest.

"It makes it more difficult for people to exercise their basic rights, if not impossible," Mr Murphy said.

"Protesting is a basic right that all of us should have in a democracy."

Source: AAP