British Columbia's children's watchdog has filed a lawsuit against the government after it introduced new legislation that prevents her from continuing to access cabinet documents related to her job.

Mary Ellen Turpel-Lafond said in a statement Tuesday that she needs the material to help her complete an audit and review of a government program involving thousands of children and youth who live with relatives.

Turpel-Lafond's office issued the statement, saying the top bureaucrat will not be commenting publicly because the matter now is now before the courts.

"I have applied to the court for an order to compel government compliance with their obligations under the Representative for Children and Youth Act," Turpel-Lafond said in the statement.

"I remain open to discussions to resolve the issue but have exhausted all other options to get the material necessary to complete an audit and review of a vital program that impacts close to 5,000 children and youth in B.C."

Children's Minister Mary Polak called the lawsuit a waste of time and money.

She said Turpel-Lafond must go through the same steps as other independent officers such as the auditor general in order to gain access to cabinet documents.

"I think it's a waste of scarce resources when she could have just as easily entered into the same kind of agreement that any other independent officer would enter into in order to view cabinet materials," Polak said.

Attorney General Mike de Jong said last week that unlike the auditor general, Turpel-Lafond has refused to sign a protocol that says she will not publicly disclose cabinet documents.

However, Turpel-Lafond has so far been given access to such material to prepare reports on issues involving vulnerable children, many of them in government care.

She said last week that as a judge on leave from her position, she would not disclose private information and agreed to such terms when she started her job as a child advocate three years ago.

Turpel-Lafond said then that the new legislation deters her from assessing how top levels of government are doing when it comes to protecting children.

She said the legislation muzzles her ability to fully examine cabinet documents and make recommendations for how things can be improved.

The NDP has criticized the government for stripping Turpel-Lafond's powers after being slow to act on many of her recommendations.