Toronto police reportedly cloned Bruce McArthur’s computer – what does that entail?

As authorities came closer to arresting alleged serial killer Bruce McArthur in relation to a series of disappearances in Toronto’s LGBTQ community, they executed a number of warrants aimed at getting digital and physical information about him — including reportedly cloning his computer in secret.

McArthur was arrested in January and charged in connection with the deaths of eight men. Police searched a multitude of properties for the remains of the men, including properties McArthur worked on as a landscaper.

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According to police documents unsealed earlier this week, the warrants include requests for documents from several companies, including Rogers, Yahoo! and Air Canada, along with tracking warrants and general warrants.

The investigation also included a covert operation to clone McArthur’s computer on Dec. 4, the Toronto Star reported.

Digital forensic expert Ryan Duquette, a former Peel Regional Police officer and founder of digital forensics firm Hexigent Consulting, said police would have needed what’s called a general warrant that has received judicial authority to clone a computer.

(Documents showed Toronto police executed a general warrant in early December 2017, but the details of what was covered under that warrant were sealed by the court.)

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“General warrants are used for a variety of different things – and the grounds that you need to get a general warrant are very, very stringent and a judge has to be very assured of what is going to happen,” Duquette explained.

To clone a computer, you would have to have access to the computer. To access a suspect’s device, Duquette said there are a variety of ways this can happen, including asking a landlord for access to the suspect’s home or other situations when the device is out of the suspect’s hands.

“But most often, it’s done by law enforcement just going in very covertly and out. They get what they need and then they leave,” Duquette said.

Cloning a computer is basically the same as taking a copy of that computer on an external device – for example, an external hard drive.

The general public might make a clone of their computer to keep a copy in case of corruption or damage. (Like Time Machine, if you’re an Apple user.) There are many readily-available software options for this.

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You may be wondering: Why not just use a search warrant and take the computer instead of making a copy?

Duquette explained that there could be a few reasons. First, a search warrant would alert the suspect to the investigation and second, since a general warrant is more specific, police or law enforcement might not have enough evidence to warrant a search warrant.

Cloning doesn’t allow police to do any type of “live interception” – that means police wouldn’t have been able to see emails or messages in real time.

That requires a separate type of judicial authority – more than the general warrant offers.

Even if the computer contained passwords to emails or messaging applications like Facebook, police wouldn’t be able to legally look at those sites.

Police instead would take a copy of the computer and then do analytics on the information and files on the computer.

If the computer is encrypted, officials would still need to crack the code before they’re able to get in.

In the case of McArthur, pictures off his computer were used as evidence to charge him with murder, sources told Global News at the time.

McArthur is currently remanded in custody until another court date on June 22.

The charges have not been proven in court.