Career
He represented the electorate of Price as an Australian Labor Party member of the South Australian House of Assembly between 1985 and 2001. In late 2001 he became an independent in the lead up to the February 2002 State Election, where he lost the reformed seat of Cheltenham to Jay Weatherill. De Laine was elected to the seat of Price on 7 December 1985.
In 1998 the seat of Price was heavily altered in a redistribution and renamed Cheltenham.
In August 2001 De Laine was defeated in an Australian Labor Party pre-selection ballot which saw Jay Weatherill take the pre-selection. On 15 August 2001 De Laine quit Labor and announced he would run as an independent at the next state election.
In the 2002 election De Laine stood as an independent and was defeated, with 9.7% of the primary vote.