The Attorney General is the Crown's lawyer and, as with any lawyer, is instructed by his or her clients. The respondents in the Amnesty International and BCCLA judicial review at Federal Court are the Minister of National Defence--i.e., the government--and General Rick Hillier, Chief of the Defence Staff. So it will be they who are instructing the Attorney General.
On May 17th, 2007. See this statement in context.