Federal Attorney-General George Brandis said he would make the change after a request was made by NSW Premier Mike Baird.

The request was prompted by the shooting of NSW Police accountant Curtis Cheng by a 15-year-old boy who has been linked to Islamic extremism.

"The Parramatta shooting demonstrates that 14 is not too young for these control orders," Senator Brandis said.

Control orders stop people from accessing defined location or communicating with certain people, accessing the internet, and may require people to wear a tracking device.

Currently, the orders can be issued to anyone older than 16 if authorities believe they pose a danger to the community.

ACT Attorney-General Simon Corbell said he was concerned by the federal government's proposal.

"These changes are unlikely to receive the support of the ACT government," he said.

"The evidence of indoctrination of young people alone is not sufficient to justify reduce the age limit for control orders."

Mr Corbell said there were more appropriate mechanisms to ensure public safety such as engagement with families and care and protection measures to supervise children who display a propensity towards radicalisation.

He said obtaining a control order for a 14-year-old would be difficult as a court would need to be satisfied the person was intent on committing terrorism.

"People who are 14 are recognised as having diminished legal responsibility compared to an adult," he said.

"Everyone's interest is in trying to protect our community, but there are some fairly important issues of the way our law operates when it comes to young people."

The NSW Council for Civil Liberties has also criticised the proposed lowering of the control order age threshold.

"The proposed laws are undoubtedly going to be in breach of human rights standards," president Stephen Blanks told the ABC.

"The idea of detaining 14-year-old children for questioning without charge, and secretly for long periods of time, should be obviously unacceptable to the whole community."