An Ontario man convicted of trafficking handguns has been acquitted with a Supreme Court of Canada ruling that finds the text messages used to charge and prosecute him should have been considered private.

In a 5-2 ruling, the majority of justices found Nour Marakah had a reasonable expectation of privacy in the messages sent to his accomplice, and that the texts used as evidence to convict him violate his charter right to be protected against unreasonable search or seizure.

But Chief Justice Beverley McLachlin said that privacy expectation is not automatic, and must be assessed in "the totality of the circumstances."

In this case, Marakah had made several requests for the text messages to be deleted from his accomplice's iPhone.

In a dissenting opinion, Justice Michael Moldaver said Marakah had "no control whatsoever" over the texts sent to and received by his co-accused.

"To say that Mr. Marakah had a reasonable expectation of personal privacy in the text message conversations despite his total lack of control over them severs the interconnected relationship between privacy and control that has long formed part of our Section 8 jurisprudence," he wrote.

While this case focused on the issue of text messaging privacy as it relates to charter protections against unreasonable search and seizure, some see the ruling as a victory for privacy protections for all Canadians.

'Broad and important implications'

Christine Lonsdale, a lawyer representing the Canadian Civil Liberties Association, an intervener in the case, said the ruling has "very broad and important implications" for the public.

She said it means all Canadians can expect that all text messages, when sent or received, are considered private. Without the court ruling, someone who sends an intimate message that is then shared could be "out of luck" in seeking a remedy, she said.

"The court here has taken hold, embraced the challenge of the technology and caused the law to catch up with the technology, in line with Canadians' values," Lonsdale said. "Canadians can expect that their private, one-on-one communications with each other remain ones that they have a reasonable expectation of privacy."

In a factum she had submitted to the court, Lonsdale said new modes of private communication deserve the same privacy protection as more traditional forms.

"In an age of increasingly pervasive use of electronic communication, every person who uses text messages to conduct a private conversation, whether or not they are accused of a crime, is impacted by the court's analysis in this case," she said.

Messages on accomplice's iPhone

In 2014, an Ontario trial judge found Marakah guilty of seven firearms offences related to the trafficking of illegal handguns, ruling that while someone who sends a text message has a reasonable expectation of privacy, it ends when the message reaches the intended recipient.

The messages obtained from Winchester's iPhone were critical to gaining a conviction, because other incriminating evidence, including the same text messages extracted from Marakah's BlackBerry, was deemed inadmissible.

At that point, the text message is no longer under control of the sender, but is under the complete control of the recipient, the judge ruled.

Unreasonable search and seizure

The respondent, the attorney general of Ontario, argued there should be no such expectation of privacy once a text has been sent.

"Having knowingly relinquished control over the messages to a recipient — who, in his or her sole discretion, can retain them, share them, copy them, or post them online — the sender cannot sensibly claim an expectation of privacy over them," its factum reads.

Marakah's lawyers, Mark Sandler and Wayne Cunningham, had argued that interpretation runs counter to the broader public expectations to ensure privacy protection for digital communications.

"This is contrary to societal expectations and norms, and leads to highly problematic consequences," it reads, citing the example of when nude or intimate images have been shared without consent of the sender.