The first guidelines for public office holders regarding conflict of interest were issued in 1973 by Prime Minister Trudeau; the first formal Conflict of Interest and Post-Employment Code for Public Office Holders was issued by Prime Minister Mulroney in September, 1985, and was reiterated by subsequent prime ministers. Although the Code had no basis in law or regulation, compliance was a condition of holding public office; those who breached it risked consequences ranging from demotion and public shame to criminal investigation.
The Trudeau era guidelines were administered by "Standard of Conduct Advisory Group", created in 1974. This group was the core of the "Conflict of Interest Advisory Group", which developed within the Department of Consumer and Corporate Affairs in the 1980s, and was placed under the authority of the Assistant Deputy Registrar General. The ADRG function (including conflict of interest administration) was transferred to Industry Canada in 1993. The ADRG's Office was replaced by the Office of the Ethics Counsellor in 1994, when Prime Minister Chrétien created this new function and issued his COI Code. The mandate of the original Office of the Ethics Counsellor was set out in the Conflict of Interest and Post-Employment Code for Public Office Holders.
The Parliament of Canada Act was amended in 2004 (S.C. 2004, c. 7) to establish the Office of the Ethics Commissioner; as such, the former Office of the Ethics Counsellor was dissolved in May 2004. The new Ethics Commissioner was to perform the duties and functions assigned by the House of Commons regarding the conduct of its Members and to administer any ethical principles, rules or obligations established by the Prime Minister for public office holders. At this juncture, the function of administration of Conflict of Interest and Post-Employment Code for Public Office Holders moved out of Industry Canada, and the new Commissioner operated as an Officer of Parliament.
With the coming into force of the Conflict of Interest Act (contained in the Federal Accountability Act) on July 9, 2007, the Office of the Ethics Commissioner was dissolved. The new legislation provided for the creation of a new position the Office of the Conflict of Interest and Ethics Commissioner. The Conflict of Interest Act enshrined in legislation the Conflict of Interest and Post-Employment Code for Public Office Holders. In addition to the administration of this Code (incorporated in the new Conflict of Interest Act), the Conflict of Interest and Ethics Commissioner is also responsible for the administration of the Conflict of Interest Code for Members of the House of Commons.