A visually striking anti-abortion protest on Parliament Hill technically broke several rules on the use of the public space, but federal officials made special exceptions to allow the event to proceed anyway.

The group was permitted to stake 100,000 small flags on a strip of the front lawn of the Hill early on Oct. 2. The mini-flags­ — blue for males, pink for females — represented the "approximately 100,000 preborn children terminated through abortion each year in Canada," said organizers.

But the posted rules governing use of Parliament Hill allow events only on the main walkway between the Centennial Flame and the Peace Tower, with any spillover directed onto the main lawns rather than on the strip of lawn along Wellington Street where the flags were placed.

The rules are also strict about "fixtures," including a prohibition against planting anything in the ground: "Affixing, hanging or attaching any item to the buildings, grounds, walkways, pillars, statues, monuments, trees, or other structures, or piercing the ground within the Hill Precinct, is prohibited."

Event organizer Andre Schutten, a lawyer with the Association for Reformed Political Action, asked in June for permission to plant the 100,000 flags on the "entire front lawn," adding that no graphic images, speakers or stages were planned.

"This event is a silent, peaceful and tasteful demonstration of a statistical fact regarding elective abortion in Canada," Schutten wrote to an interdepartmental committee that oversees use of Parliament Hill. The committee of public servants is chaired by Canadian Heritage and includes representatives of the House of Commons, Senate, RCMP, the Parliamentary Press Gallery and the Privy Council Office.

Flag display initially rejected

The panel responded on July 11, saying demonstrators could carry signs but the proposed flag display would not be permitted, say documents obtained by CBC News under the Access to Information Act.

Schutten said in an interview that the committee initially wrote him to say "Parliament Hill is a public space, it belongs to all Canadians, and … putting up a display like this … would monopolize that space, especially the green space on Parliament Hill."

Schutten says he then suggested using only one part of the front lawn, and invited ideas from the committee — members of whom soon suggested using the strip of lawn running beside a stone wall that stretches along Wellington Street. Tourists then could still take pictures of the Centre Block and Peace Tower without the 100,000 flags in the foreground.

He also told the committee he had contacted three horticulturalists in southern Ontario who were ready to affirm that the flags and their wire supports, known as "irrigation flags" in landscaping, would not harm the lawn.

The committee acceded to the request, after consulting the National Capital Commission, the federal agency that maintains the grass.

Against usual practice. — Internal RCMP assessment of flag display on Parliament Hill

"They concurred the flags would not cause any damage," Canadian Heritage spokesman Tim Warmington said in an email to CBC News.

"The prohibition on piercing or planting larger objects such as poles or supports is in the rules because such items can cause damage to the lawn; the organizer and the committee both determined that the lawn would not be damaged in this particular case, so the request was allowed."

And so about 100 volunteers began planting the small flags at 7 a.m., removing them by 4:45 p.m. that day, all under the watchful eyes of the RCMP (weeks before the Oct. 22 shooting on the Hill).

RCMP cite 'ambiguity'

"It seems that against usual practice permission has been granted to place the 100,000 irrigation flags on the ground for the day," says an internal Mountie report on the event, citing an "ambiguity."

NDP Leader Tom Mulcair stopped to speak briefly with a volunteer that day, and five days later told a Planned Parenthood meeting that the person indicated the group had received "special" permission.

Schutten, who bought the flags wholesale, said there are no immediate plans to reprise the event in 2015, saying the 100,000 flags were later distributed in lots of 10,000 and given to affiliate groups in Ontario, Manitoba, Alberta and British Columbia for smaller installations.

"It wasn't meant to be an annual thing," he said.

Warmington said the Canadian Heritage-led committee meets twice a year, and otherwise reviews proposals by email. There is no selection or appointment process for membership.

"To the best of our knowledge, the committee has not received any other request to plant flags on the ground," he said.

Committee spokeswoman Catherine Gagnaire added that "every effort is made to accommodate groups."

Marisa Monnin, spokeswoman for Heritage Minister Shelly Glover, said, "We'd like to reiterate that all individuals serving on the committee are public servants and that this decision was made independently."

On Friday, Mulcair said it was important for the rules be applied in the same way for everyone.

"This is quite clearly a case where the rules were bent," he said. "Mr. Harper is always saying he's not going to try to get back into the abortion debate. But this clearly was a political statement to allow this group to squat that much territory on Parliament Hill."

There are separate strict rules governing displays in the Centre Block building itself, containing the House of Commons and the Senate chamber, including one that forbids MPs and Senators from displaying the Canadian flag in their office windows.

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