Born and raised in
Hastings, Duff was educated at
Hastings Boys' High School. He then studied at the
University of Canterbury in
Christchurch, and became a secondary school teacher. He began teaching at
Burnside High School in 1973 and was New Zealand's first openly gay secondary school teacher. and helping to launch Gay Liberation Christchurch, both in 1972. Duff was also active in the
Post Primary Teachers' Association, serving as its junior vice-president between 2005 and 2007, president from 2007 to 2009 and 2011 to 2013, and senior vice-president between 2009 and 2011 and from 2013 until his death in Christchurch in 2015. ==References==