He was the first New South Wales Minister for Aboriginal Affairs and was responsible for some of the first legislation that recognised the obligation to financially compensate indigenous Australians for the loss of their land.

Aged 12, the family moved to the New South Wales north coast[2] regional centre of Coffs Harbour where he completed his secondary schooling.

[3] A prominent figure of the left-wing,[2] Walker was elected as the member of the New South Wales Legislative Assembly from 1970 to 1988, representing Georges River for the Australian Labor Party.

[4] During his term as Attorney General between 1976 and 1983, Walker was notable for a reform agenda that included the first state-based land rights legislation, repealing the Summary Offences Act (NSW), which allowed police to act with impunity against the poor and homeless, major changes to the so-called "rape" laws, and opening up corporate fraud to greater scrutiny.

[5] Walker's state and federal career both ended the same way that of him losing his seat at the same time that a sitting government, which he was a minister of, had been defeated.

[7] A memorial lecture is held each year to commemorate Walker's life and achievements by the NSW Society of Labor Lawyers.