On September 11 last year, Turner visited Shirley Library and cast an 'Advanced Vote' in the General Election by signing a 'Declaration by Special Voter' and submitting a completed ballot paper.
Over the next 10 days, he cast a further six advance votes at various polling stations around the city.
On election day, Turner cast four 'Special Votes' at various city stations.
"In all 11 instances, that vote cast by the defendant was for the same political party, and the same local electorate candidate," the police summary of facts says.
Later, he told police he didn't know it was wrong to vote more than once.
Turner was charged with personation, which carries a maximum penalty of two years in jail or a $40,000 fine.
Judge John Strettell today said the offending "strikes at the heart of society" and as to how elections are conducted.
However, the judge noted that Turner had a "limited understanding" of his actions and granted him a conviction and discharge.
If Turner was to reoffend within six months, he would have to come back to court and be resentenced.