When Prime Minister Stephen Harper’s government killed the long-form census, it insisted that Canadians needed to be shielded from “coercive and intrusive” assaults on their privacy.

Yet that is just what the Supreme Court has now authorized by ruling that police are allowed to seize a suspect’s cellphone upon arrest and conduct a warrantless search of its contents. If that isn’t a coercive and intrusive invasion of privacy, what is?

This unwelcome decision, by the narrowest of 4-3 margins on a deeply split court, gives the police far too much power to plow into our private lives just because they suspect we have committed an offence. Far more people are charged with crimes than are convicted. As the Star has argued before, Canadian law is clearly lagging behind public expectations when it comes to privacy.

Cellphones aren’t backpacks, briefcases or pockets, where a suspect might be hiding a gun or knife, illegal drugs or stolen goods. Cellphones are different. They pose no risk. And given the vast amount of data we store on them they are yawning portals into our private lives. The police may find it convenient to seize and search them, to identify accomplices or for other purposes. Certainly they did in the case of Kevin Fearon, the robber whose warrantless search triggered this ruling. But the common law power to search “incident to arrest” shouldn’t automatically cover cellphones.

Much like the desk drawers, filing cabinets or safes in our homes, our cells should not be cracked open without a court order.

If the Conservatives are serious about honouring Canadians’ legitimate expectations of personal privacy they should look to passing legislation requiring the police to get a warrant before searching seized cellphones or similar digital devices — except in urgent circumstances where public safety is at risk.

Cellphones, smart phones, tablets and similar devices routinely contain names, phone numbers, addresses of family, friends and business acquaintances. They can contain medical information, bank records, memos, diaries and calendars. Photos and videos. Internet browsing histories. Facebook and Twitter information. They are deeply personal records. Our laws should reflect that.

In a nod to just how invasive cell searches are, the court has set out conditions as a firewall against abuse. Police can’t “rummage … at will.” The arrest must be lawful. The search must be prompt. Police must “tailor” the search to a law enforcement objective. And they must keep a record of what they looked into, and for how long.

The court is well aware of the potential for abuse. Given that risk, the firewall we should be relying on is a judge’s considered order.