The groups have begun an application in Federal Court challenging the National Capital Commission's decision to break ground for the project.
The lawsuit by the Royal Architectural Institute of Canada, Heritage Ottawa, and architects Barry Padolsky and Shirley Blumberg alleges that the NCC violated its own procedures and acted illegally in deciding to prepare the monument site, despite having no finalized and approved design for it.
The monument has sparked controversy because it is seen as an ideologically driven project by the Harper government that would be out of sync with its surroundings.
The NCC — an unelected body of federal appointees that oversees land in and around the national capital — has ten days to oppose the application.
The commission said Thursday that the monument would occupy about two-thirds the space on a prime piece of land near the Supreme Court of Canada than originally planned, and would only be half as tall.
Legal action was necessary, the groups said in a statement, not because of opposition to the monument itself, but because it's a bad location and the NCC didn't hold proper public consultations before going ahead with the project.
"The applicants do not oppose the commemorative intent of the memorial and believe that other appropriate sites exist," the groups said in a news release.
"They are concerned that the precipitous decision of the NCC to approve groundbreaking runs contrary to the National Capital Act and the long-term vision and plan for the district. They believe that any such decision requires meaningful public consultation given the significance of the site to Canada’s heritage and democracy."
The Harper government wants the monument constructed on land adjacent to the high court that was originally set aside for a new Federal Court building.
But a number of groups, including the City of Ottawa, the Canadian Bar Association, the Chief Justice of the Supreme Court of Canada and various architectural institutes, are opposed to its erection.
The commission said Thursday that further design refinements are expected before the project reaches the final approval stage, expected in the coming months.
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