Prior to his election, Carbines was chief-of-staff to Labor MP and Minister for Education Bronwyn Pike, whilst also serving as a councillor on the City of Banyule council.[4] In 2009, he initially lost pre-selection for the seat of Ivanhoe, however this decision was subsequently overturned when the then-premier, John Brumby, personally intervened to pre-select Carbines instead of the sitting MP, Craig Langdon.[5] Langdon subsequently resigned from the parliament with the election a few weeks away. Due to the cost and difficulty involved in holding a by-election, none was called and the seat remained vacant until Carbines was elected.
