You support a group of peace activists who lobby against Canadian involvement in Afghanistan. Then they ask you to run for political office. Do you accept?
I cannot accept. Vatican II, in its Dogmatic Constitution on the Church, Lumen Gentium, differentiated between the roles of the laity and clerics. In number 31 of that document, the Fathers of the Council indicated that clerics are "principally and expressly ordained to the sacred ministry". They went on to say that "it is the special vocation of the laity to seek the kingdom of God by engaging in temporal affairs". Mindful of this, the Code of Canon Law, in number 285 (3) states that "Clerics are forbidden to assume public offices which entail a participation in the exercise of civil power."
It is definitively and without any qualification whatsoever, that clerics are forbidden to hold any public office which would entail the exercise of public authority. Many offices are prohibited here, including that of city councilor or mayor, member of parliament or premier, to name but a few. Advisory positions could be permitted, but, in all cases, it would be wise to contact the diocesan bishop (or the provincial in the case of a religious) beforehand. Canon 288, unless particular law states otherwise, exempts permanent deacons from this prohibition, but the deacon should consult with his bishop before undertaking such action because his own ministry could very well preclude holding such offices.
Our involvement in politics through holding public office could create confusion, among the people we serve, in terms of the Churchs mission. It is for that reason that priests keep a certain distance from political office, so that we can preach the Gospel and celebrate the sacraments, independent from any secular authority. We are called to be builders of unity, bringing Christs message in its entirety to all. Such a task would be made extremely difficult if we assumed an office which, at times, could be partisan.