We've had a policy that I can track at least back to 1990. We regularly review our policies, generally on a five-year cycle. This policy was just revised in February 2010 mostly to reflect the changes to the Canadian Human Rights Act. There were a couple of discriminatory areas that were added such as family status as an example. So we made sure that our policy reflects the current legislation.
On March 5th, 2013. See this statement in context.