Trudeau and his government were also the architect of the Charter of Rights and Freedoms, which was what used to declare this law unlawful. Trudeau was a very controversial Prime Minister, but he wasn't totally bad.
Coryoth writes "The Canadian parliament has voted against renewing anti-terror laws that had been introduced after September 11, 2001. The rejected laws included provisions to hold terror suspects indefinitely, and to compel witnesses to testify, and were in some sense Canada's version fo the Patriot Act. The laws were voted down in the face of claims from the minority Conservative government that the Liberal Party was soft on terror, and despite the fact that Canada has faced active terrorist cells in their own country. The anti-terror laws have never been used, and it was viewed that they are neither relevant, nor needed, in dealing with terrorist plots. Hopefully more countries will come to the same conclusion."