The Canadians seem to be having their own version of the Karl Rove/Harriet Miers/Josh Bolten controversy that arose in during the Bush administration (when these White House officials asserted immunity from having to appear before congressional committees). The Canadian government has declared only cabinet ministers, not their political staffs, can be called as witnesses before parliamentary committees.
Generally speaking, I presume the Canadian Parliament has the same inherent powers to call for testimony and records as does the Congress. According to the Canadian House of Commons Procedure and Practice Manual, standing committees have the power to issue a summons for any person located on Canadian soil, with certain recognized exceptions. These include the Queen (no surprise), the Governor General and provincial lieutenant-governors (who I think are the Queen’s representatives) and members of either Canadian provincial or federal legislative bodies.
Since parliamentary committees are not permitted to summon Members of Parliament (at least not without the specific authority of the House), it would seem that they cannot not compel the appearance of the prime minister or a cabinet minister (who are Members of Parliament). In this case, however, the government is arguing that the committee must call the minister, rather than his or her political subordinates. The basis of the argument, which I don’t fully understand, has something to do with the concept of “ministerial responsibility,” a system in which it is only the ministers (and not their subordinates) who are considered responsible to both the Parliament and the Canadian people. A government spokesman distinguishes this system from that in the
Normally this type of issue would not arise in the Canadian system because the government and the Parliament would be controlled by the same party. However, the current Conservative government has only a plurality in Parliament, and this apparently means that the opposition effectively controls at least some of the standing committees. The latest controversy involves a request to a government official to testify before the House of Commons committee on access to information, privacy and ethics, which is chaired by a Liberal Democrat.
What happens if the government official refuses to appear and the parliamentary committee refuses to accept the failure to appear? Like the Congress, the Canadian Parliament has the inherent power to punish for contempt, and to imprison recalcitrant witnesses. The last time this authority was used, however, was 1913.