Canadians' digital communications should get the same privacy protection as voice conversations during police investigations, following a new ruling from Canada's top court.

The Supreme Court ruled Thursday that police need a wiretap order to seize your text messages from your wireless provider as they are sent and received.

In her reasons for judgment, Justice Rosalie Silberman Abella, supported by two other judges, wrote that the only practical difference between text messaging and traditional voice communications is the transmission process.

"This distinction should not take text messages outside the protection to which private communications are entitled," she said.

General vs. wiretap warrants Police need to meet a higher standard to obtain a wiretap warrant compared to a general warrant. That is because the law recognizes that private conversations often involve sensitive information and deserve special protection. In addition, wiretapping is a covert way of obtaining information, and those being wiretapped have less control over their information that they do over, for example, documents that might turn up in a home or office search. Wiretap warrants typically can only be obtained for certain offences and police have to show they couldn't get the same type of information using a different investigative technique. General warrants can be obtained for a broader range of offences, and police only need to show they have grounds to believe an offence took place.

Two other judges agreed in part and in the result, while two remaining judges dissented.

The decision overturns a lower court ruling against Telus Communications that required the company to hand over copies of all the text messages sent and received by two of its customers each day over a two-week period after it was served with a general warrant by police in Owen Sound, Ont.

Telus had appealed the ruling. The phone provider argued that seizing the messages would constitute "interception" of the communication and would therefore require a wiretap warrant. That is more difficult for police to get than a general warrant, because of special privacy provisions in the Criminal Code protecting private communications.

Private communications

Justice Thomas Albert Cromwell, one of the two dissenting judges, wrote that while there is "no doubt" that text messages are private communications, his conclusion was that the investigative technique in this case was not an interception of private communications. Therefore a general warrant, rather than a wiretap order, was the appropriate authorization.

Cromwell came to that conclusion because the copies of the text messages that police wanted to obtain from Telus were not the copies sent and delivered by Telus customers, but copies kept in a database by Telus for 30 days for "troubleshooting purposes."

"The general warrant did not require Telus to intercept communications, but to provide copies of communications that it had previously intercepted for its own lawful purposes," Cromwell wrote.

Other providers don't keep texts

A general warrant can only be used if police show that no other provision of the Criminal Code, such as those pertaining to wiretaps, or any other legislation would allow them to use a given investigative technique. The two judges who partly supported the judgment agreed that the investigative technique that police were using in this case was "substantively equivalent to an intercept" and therefore a general warrant couldn't be used.

Abella also noted that most wireless providers other than Telus do not keep a database with copies of their customers' text messages. Therefore, police targeting text messages from customers of other wireless providers would need a wiretap authorization.

"This creates a manifest unfairness to individuals who are unlikely to realize that their choice of telecommunications service provider can dramatically affect their privacy," Abella wrote.

The case began when Owen Sound police obtained a warrant in March 2010 ordering Telus to provide from its database copies of all the text messages sent by or addressed to two of its subscribers during the first two weeks of April that year. The messages would be handed over to police daily and might therefore include messages that the users themselves had not necessarily received.

An Ontario Superior Court judge ruled against Telus in 2011. It agreed with Crown lawyers that handing the messages over to police did not constitute "interception," because the copies of the text messages being handed over to police were not intended to be transmitted and were not created and stored for a purpose related to transmitting the messages.

Telus, interveners pleased

Scott Hutchison, Telus's lead lawyer for the case, said the company appealed because it wanted to make sure privacy protections in the law designed with voice communications in mind became clearer with respect to new communications technologies such as text messages and email. Meanwhile, the Charter of Rights and Freedoms has led to an evolution of police powers, he added.

"The law was having trouble keeping up with all of that."

Hutchison said Telus is happy with the Supreme Court's decision.

Abby Deshman, director of the public safety program at the Canadian Civil Liberties Association, one of the interveners in the case, said the ruling "really upholds the existing privacy protections in the Criminal Code for new modes of communication like text messaging."

Tamir Israel, a lawyer for the other intervener, the University of Ottawa's Samuel-Glushko's Canadian Internet Policy and Public Interest Clinic, said he is also pleased with the judges' ruling.

"They recognize that Canadians view these types of text message interchanges as very similar to voice calls," he said.

The fact that the court recognized the principle that private communications should be offered the same protection regardless of the type of technology used to conduct them "will help down the road when we start looking at other types of communications that have similar challenges," he added.

For example, Israel said, like text messages, email and instant messages are often stored temporarily on servers to ensure they get delivered. Temporary storage allows the server to try delivering the message later if there is a network issue at the original time of transmission, for instance. However, had the court ruled against Telus, those other types of communication may have been more vulnerable to police surveillance.

Deshman also thinks the privacy protection upheld in this case is relevant to other cases where police approach communications service providers and want access to customers' private digital communications. However, she noted that it applies specifically to cases where police want future access to messages that have not yet been exchanged rather than records of past exchanges.