Canada's spy agency has explicitly told its officers to describe people in "a fair and precise manner" when passing information to other countries, especially those with poor human rights records.

The formal directive came last November from the deputy director of operations at the Canadian Security Intelligence Service, The Canadian Press has learned.

That was one month after a federal inquiry into the torture of three Canadians lambasted CSIS for carelessly labelling suspects.

In his report released one year ago this week, former Supreme Court justice Frank Iacobucci found Canadian officials contributed to the brutalization of Ahmad El Maati, Abdullah Almalki and Muayyed Nureddin by sharing information, including unfounded accounts of extremist links with foreign intelligence and police agencies.

Iacobucci concluded all three were tortured behind bars in Syria and, in the case of El Maati, in Egypt as well. All deny any involvement in terrorism.

The former judge said CSIS was "deficient" in definitively describing El Maati as "an individual involved in the Islamic extremist movement."