After each election to the Scottish Parliament, at the beginning of each parliamentary session, Parliament elects one MSP to serve as Presiding Officer, the equivalent of the speaker (currently Tricia Marwick), and two MSPs to serve as deputies (currently Elaine Smith and John Scott). The Presiding Officer and deputies are elected by a secret ballot of the 129 MSPs, which is the only secret ballot conducted in the Scottish Parliament. Principally, the role of the Presiding Officer is to chair chamber proceedings and the Scottish Parliamentary Corporate Body. When chairing meetings of the Parliament, the Presiding Officer and his/her deputies must be politically impartial. During debates, the Presiding Officer (or the deputy) is assisted by the parliamentary clerks, who give advice on how to interpret the standing orders that govern the proceedings of meetings. A vote clerk sits in front of the Presiding Officer and operates the electronic voting equipment and chamber clocks.