A Vancouver father's battle to let his young children ride transit to school by themselves has tapped into a vein of modern-day parenting angst worldwide.

But there is more to this tale than stolen childhood autonomy.

Adrian Crook blogs about urban condo life and says he spent two years training his children — aged seven to 11 — to take the bus on their own, which experts say is statistically safer than driving them to school.

But somebody complained.

To his shock, provincial child welfare officials investigated and wrote Crook a letter saying he couldn't let unsupervised children under age 10 out in the community alone.

His plight drew outrage from parents calling it an example of authorities stealing children's freedom, touching a nerve in the modern debate over parenting styles: helicopter versus free-range.

It's important to note, this situation is quite specific.

The Crook family

Crook shares custody of his five children and admits their mother probably doesn't approve of letting their children ride transit alone. Social workers also cited him for physical discipline — specifically ear pulling.

Provincial child welfare officials investigated after Adrian Crook let his children ride transit alone and made him promise to supervise any child under age 10 in the community. (Adrian Crook/Instagram)

The rules in Canada

The Crook situation aside, here are the rules in Canada for parents who want to leave children alone at home or on the bus: There aren't any.

The Ministry of Children and Family Development confirmed with CBC there is no specific age legislation in B.C. or in Canada that stipulates when a child can be left unsupervised.

It depends on a lot of factors.

If the ministry gets a complaint, then social workers assess the situation.

They consider a series of issues, ranging from the child's comfort level to the time of day, safety measures in place, the child's maturity, how long the child was left, whether they were alone, whether they had access to responsible adults and a way to contact parents and any historical concerns affecting the family.

Adrian Crook lives in a condo downtown with five children and feels that it is important they learn to navigate transit on their own. (Adrian Crook/5 Kids 1 Condo)

"We look into the circumstances, assess the risk to the child (or children) and the parent's ability to provide care," the MCFD told CBC in an email.

In the end, Crook was deemed a "safe" parent, but he recognizes why others, including his ex-wife, might disagree.

"I don't think she likes it much. We have differences of opinion about urban versus suburban life."

The case has opened up fears among many parents. Some of them now fear they'll be targeted by social services for letting a child walk to school alone.

Is 10 the magic age?

Across Canada, courts have wrestled with the issue.

A 2015 B.C. Supreme Court ruling dealt with a Terrace mother who left her eight-year-old unsupervised after school.

The judge cited experts on the "risks to children under the age of 10 due to their limited cognitive ability."

While this has become a loose guide, no real rules exist to help parents determine when it's legal to let their child walk or ride a bus to school alone.

There are no rules against children under 10 riding transit alone in Vancouver, but one father was told he needed to supervise his underage bus riders.

A simple age limit is inappropriate, because it gives a false sense of security, says Dr. Mariana Brussoni, a University of British Columbia expert in child development and injury prevention.

Children do not magically reach the maturity to manage solo at the same age — for some it may be younger, others older, she said.

Every child is different and she says risk needs to be introduced incrementally.

Brussoni was disturbed to hear a case where children were not allowed to ride the bus alone when it seemed like a "textbook" case of how to do this right.

"As a parent, this scared the crap out of me. I'm an expert in this, and I am clear on how I want to raise my children. I don't want social services interfering with that."

She allows her nine and 10-year-old to ride the bus without supervision.

So far, she says, social services have left her alone.