More Harper Hypocrisy.
First, this is showing how crass Harper is. The Government of Canada is an institution that transcends whoever happens to be in office at the time. It is part of the role of prime minister to represent the institution. This means that if you're the prime minister of the day, and the GOC has to admit culpability for something, you take one on the chin for the team. You do not blame a previous holder of the office in what appears to be a cheap attempt to score some political points. Not even Brian Mulroney tried to blame a previous government when he apologized for the treatment of Japanese Canadians during WWII. It would appear that Stephen Harper is no Brian Mulroney, and isn't it scary to think that one would compare someone negatively to Mr. Mulroney. In this instance, Harper has shown that he cares little for the institution of government and only about his hanging on to power. This means that Canada's "new" government is no better than Canada's "old" government. Harper isn't giving Canadians much reason to be re-elected next election since his MO seems to be to blame the Liberals for everything and then say "vote for me, I'm not the Liberals". This only works if you don't act like the Liberals, or in this case, even worse than the Liberals.
It gets even more laughable (if such a thing could be funny) in that while the previous government was trying to free Maher Arar from a Syrian prison, Harper basically called Arar a Terrorist while complaining that the Liberal government was doing too much to help him. This makes Harper just as culpable as the previous government, possibly more so as the previous government was at least attempting to get Arar back. I note that Harper failed to apologize for his accusations in his letter and speech. So basically Harper apologized for the previous governments bungling of the file, while all the time quietly ignoring the fact that if he had been PM at the time, Arar would likely still be in a Syrian prison today. It all makes the apology rather hollow.