The Crown, however, argued that Canadians cannot refuse to comply with legitimate government obligations simply on the basis of moral disapproval or speculative security fears.
Janet Churnin has been charged with violating the Statistics Act and, if convicted, could face a $500 fine and/or three months in jail.
"Whatever happens will happen," the soft-spoken senior said with a shrug outside a Toronto court. "I still wouldn't change anything."
At the heart of Churnin's worries lies defence company Lockheed Martin's involvement in the census process, which she learned about only after reading a newspaper article flagged by a friend in 2011.
Statistics Canada has said the government contracted Lockheed Martin to provide software for its census operations in 2003, and used the custom-built systems for both the 2006 and 2011 census.
Churnin worried information on Canada's population was at risk because she thought it could be accessed by Lockheed Martin, or even the U.S. government if it made the corporation turn over the data under its Patriot Act.
"Your privacy is not considered at all," she told court when explaining her decision to refrain from filling out the census form.
"I don't believe that Statistics Canada shared information willingly. But I think that once the information got to Lockheed Martin, it could be easily accessed."
Churnin, who describes herself as a peace activist, also said she didn't want to appear to be supporting Lockheed Martin or be associated with them in any way due to their reputation as a defence giant.
Simply not filling out the census form, she said, was the most direct form of protest.
"I'm too old at the moment to go on any marches," she explained at her trial. "This is the easiest way for me to demonstrate that I don't like the census form being accessed by an American company."
A third factor in Churnin's refusal was a desire to protest the federal government's scrapping of the long-form census, which was replaced with a voluntary national household survey.
Churnin explained that her actions were not to be confused with an opposition to collecting statistics in general — in fact, she'd rather have the mandatory long-form reinstated but doesn't want a U.S. company involved in the data collection.
Crown lawyer Maria Gaspar argued that filling out the census form in no way threatened Churnin's beliefs or her ability to carry out those beliefs.
"The purpose of the census form is not to restrict expression, it doesn't even have the effect of restricting expression," Gaspar said.
"Ms. Churnin has the option to continue voicing her opposition to Lockheed Martin, her issue with Statistics Canada...any other issue that she wishes to express. The requirement to complete the form has no impact on that."
Churnin's lawyer, however, argued that her Charter rights were violated by being required to answer the short-form census because Statistics Canada didn't do enough to address her concerns.
He suggested there is the possibility Lockheed Martin could have built a "back door'' into its software, which could potentially put the Canadian data at risk.
The head of census operations at Statistic Canada testified earlier that Lockheed Martin had no access to the agency's data operation centre or its census response database.
Yves Beland also told the court that various security tests of the census processing systems concluded there was "absolutely no risk" that could not be handled by the data collection agency.
But Peter Rosenthal suggested Churnin's worries remained relevant.
"I'm not asking you to find that Lockheed Martin did anything, we don't know that they did," Rosenthal told the judge presiding over the case.
"I'm asking you to find that Ms. Churnin has the right to refuse to provide data given the way that Statistics Canada dealt with concerns that Lockheed Martin might obtain the data."
In describing his submissions as "novel arguments," Rosenthal said Churnin's rights to a reasonable expectation of privacy, freedom of conscience and freedom of expression were violated in compelling her to fill out the census form.
"It would violate her freedom of conscience because she clearly conscientiously objects to being associated with Lockheed Martin in this way," he said.
"Secondly we say that her privacy rights are violated ... because Statistics Canada was, in our view, negligent in failing to isolate the data from Lockheed Martin's possible back door approach," Rosenthal said.
"Thirdly we have a freedom of expression argument that she doesn't want to be compelled to express the data in concert with Lockheed Martin because of her conscientious beliefs."
Churnin's case is similar to that of an 89-year-old peace activist who also refused to fill out the 2011 census.
In that case, Audrey Tobias was found not guilty in October by a Toronto judge who soundly criticized the government for trying to prosecute someone who was a "model citizen.''
What makes Churnin's case different from Tobias's, according to Rosenthal, is the argument about security fears regarding Lockheed.
Tobias was in court to support Churnin on Wednesday, saying there was no other place she'd rather be.
A decision on Churnin's case is expected to be delivered on Jan. 22.
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