[1960 Code § 1.06.010]
The City Council shall consist of the Mayor and two Aldermen from each ward. The Council shall be the judge of its election and qualification of its own members. An Alderman may resign from his office. Should a vacancy occur in the office of Alderman by reason of resignation, failure to elect or qualify, death, permanent physical or mental disability, conviction of a disqualifying crime, abandonment of office or removal from office or of residence from the ward, the office may be filled at the next succeeding general election for Alderman at which time the vacancy shall be filled for the unexpired balance of the term. A vacancy for Alderman shall not be filled by special election in compliance with Section 3-4-14 of the Illinois municipal code. The Mayor, with the advice and consent of the City Council, may appoint a person to serve as Alderman in the vacancy until the next general election as provided in this section and until the person elected qualifies.