The head of the NSW Police Association has called for an urgent funding injection into mental health services after the Sydney CBD stabbings, while a senior Australian legal figure is pushing for specialised courts to tackle the issue.

As the NSW government launches a review into all aspects of the care of mentally ill man Mert Ney, who is facing charges over the death of one woman and the wounding of another, Police Association president Tony King said authorities needed to focus on stopping the problem before it becomes a criminal issue.

Mert Ney after his arrest on Tuesday. Credit:Seven News

"The lack of resources and funding for mental health services needs to be addressed urgently," Mr King said.

"The association has been calling for more support for mental health units for years and saying that police are constantly being engaged with mental health patients at all hours of the day."