Peter graduated from the University of Adelaide in 1874 with Honours in Law and was appointed to senior counsel in New South Wales in 1993. He has chaired the New South Wales Bar Association Advocacy Committee and been a member of the Legal Profession Admission Board for fourteen years.

For twenty one years, Peter was the General Editor of Ritchies NSW Supreme Court Practice. Since 2005, Peter has been the General Editor of Ritchies NSW Uniform Civil Procedure. In 2006, Peter was appointed part-time senior member of the Administrative Appeals Tribunal.