The politician, a Social Democrat councillor in Surahammar, about 100 kilometres west of Stockholm, was employed to hand out voting slips during elections on September 17th last year.
The woman has admitted taking the voting slips and putting them in a bag. She says she cannot explain why she did so, simply saying she had a moment of madness. She denies deliberately trying to affect the result of the election.
In Swedish elections, voters take a ballot paper for the party for which they want to vote and place it in an envelope.
If convicted, the woman could face a fine.