The 1971 Adelaide state by-election was a by-election held on 3 July 1971 for the South Australian House of Assembly seat of Adelaide. This was triggered by the death of state Labor MHA Sam Lawn.
Results.
The Communist Party, who contested the previous election on 4.9 percent of the vote, did not contest the by-election. Labor easily retained the seat.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align:right;" | Total formal votes
! colspan="3" style="text-align:right;" | Informal votes
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
References.
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