Susan Smith, 33, the former member for St Martins ward in the London borough of Lambeth, was sentenced to a total of 18 months. Ronald Lineker, 53, who was said to have transvestite tendencies, was jailed for three years after being convicted of two charges of indecent assault and six of unlawful sexual intercourse.
At Southwark Crown Court Judge Gerald Butler QC told Smith, who was convicted of five offences of indecently assaulting the girl, that he had no doubt she had been responsible for bringing the threesome together.
The court heard that Smith, who once served on Lambeth's social services committee, missed council meetings to take part in the sex sessions.
The girl had been unhappy at home and moved to Lineker's flat in Waterloo, south London, for three weeks in July last year. Smith would indecently assault her first, saying she was 'getting her ready for Ron'. She had been a virgin when she moved to the flat, and was terrified throughout.