A man declared mentally incompetent under a Nova Scotia law that a legal expert says is "ripe for attack under the charter" of rights has left Alberta to try to have his status overturned and fight to change the legislation.

"I want to fight my case. I want to win," said Landon Webb, 25, who voluntarily left the Kings Regional Rehabilitation Centre in Waterville, N.S., in October to find work in Western Canada.

"I don't want to just do it for myself, but for my son, my girlfriend, and for all the other people who have their rights stripped away and violated."

Webb found himself the subject of several police alerts this year that said he had gone missing. His parents claim he functions at the level of a 10-year-old boy, and were upset when he discharged himself from the rehabilitation centre, where treatment is voluntary.

Webb told CBC News that he should be free to set his own course, and opposes the Incompetent Persons Act.

"I feel that no one should have the right over someone else. I'm a person, a human being, not some piece of property. I should have my voice heard. I should be able to choose where I live, not have someone else choose it for me," he said last week as he prepared to leave Alberta.

​ Listen to Webb: ​'I am person, a human being, not some piece of property'

Read the Incompetent Persons Act

He called his treatment discriminatory and upsetting.

"To see that I was all over the news with the intellectual level of a 10 to 12-year-old, and to see all the comments people make about me? It's very upsetting, to say the least."

He said he spoke to police in Edmonton to show he was safe and not in danger. But he has since returned to Nova Scotia, and said he intends to overturn the mentally incompetent declaration.

"I'm not saying they were wrong at the time deeming me incompetent, but now that I've grown up and grown older, I expect I can prove my competency to the courts," he said, adding that the testing required to do that costs thousands of dollars.

Law contravenes charter, scholar says

Sheila Wildeman teaches law at Dalhousie University's Schulich School of Law and is the associate director of the Health Law Institute.

On Tuesday, she said Nova Scotia's incompetency act is unique in Canada. She also said the global standard makes Nova Scotia a "laggard" in Canada, she said.

"The act is at odds with modern principles of legal capacity. All of this goes to the act's arbitrariness, its overbreadth, its contravention of Section 7 of the charter that protects liberty.

"What I'd like to hear is the [Nova Scotia] minister of justice, Diana Whalen, on how the government justifies this type of legislation remaining on the books in 2015."

Nova Scotia is one of the last jurisdictions in Canada to offer a "global" declaration of incompetence, she said, and the law wouldn't likely survive a legal challenge.

Section 7 of the Charter of Rights and Freedoms guarantees "everyone has the right to life, liberty and the security of the person."

Under the act, parents or guardians must get affidavits from two physicians saying that person can be declared incompetent.

They must prove "mental infirmity" that makes that person unable to manage his or her own affairs.

She said the statement of global incapacity removes individuals' right to handle their own finances, and choose where to live, what to wear and even manage their own grooming.

'Ripe' for a legal challenge

Wildeman is "perplexed" at how you could prove such a comprehensive decision in the first place.

"That's really at the heart of the problems with the act that I think in part Landon Webb is getting at," she said. "The standard itself is ripe for attack under the charter."

But Wildeman said the act "empties your decisions of legal authority," and if the person receives close oversight from family members, the family or guardian could deny him or her access to health records or get a lawyer.

That makes it hard to build a case against the declaration. Such people can apply to end the guardianship order, but Wildeman is unaware if that would ever happen.