Lawyers and technology experts say the Internet has allowed for extensive records to be kept of one's movements and comments unlike anything in the past, but most people still don't consider the potential permanence of their words when firing off a message.
The amount of electronic data, records and documents introduced in trials can be "overwhelming," said David Fraser, an Internet and privacy lawyer with McInnes Cooper.
"There's also a tendency for people to put in email messages things that would be relatively casual that they earlier would have picked up the phone to communicate," he said.
"It's a whole lot easier to keep it than it is to make the effort to decide what to delete."
"Picking up the phone wouldn't have created a record, but as soon as (the recipient has) an email message and they're not inclined to delete it, all of a sudden you have a record."
Defence lawyer Marie Henein has grilled two female complainants on their correspondence with Ghomeshi after the alleged assaults. A third has yet to testify.
On Friday, Henein produced a racy email sent by Lucy DeCoutere mere hours after she alleges Ghomeshi choked and slapped her in 2003, as well as a handwritten letter sent a few days later in which DeCoutere wrote "I love your hands."
The "Trailer Park Boys" actress testified she didn't remember sending the email. She said firmly that the note — as well as other warm and even romantic dispatches she sent to Ghomeshi — didn't mean the alleged assault didn't take place.
Lucy DeCoutere alleges Jian Ghomeshi choked and slapped her in 2003. (Photo: Getty Images)
Ghomeshi has pleaded not guilty to all charges against him. In a 2014 Facebook post he acknowledged engaging in rough sex but said it was consensual.
While 13 years is a bit further back than most people's saved correspondence stretches, Fraser said it's increasingly common to hang on to emails forever, given that web-based clients like Gmail, Yahoo Mail and Hotmail have practically unlimited storage space.
"It's a whole lot easier to keep it than it is to make the effort to decide what to delete," he said.
Only a few lines of Ghomeshi's replies have been read out by the defence and the Crown has not indicated that it has digital dirt on the former CBC Radio host. It may not be too late for the Crown to seek a search warrant for Ghomeshi's emails, if it hasn't already, Fraser said.
"Sometimes, even when someone thinks they've deleted an email from their computer, it's not deleted."
He said it's common sense in 2016 for lawyers to ask themselves if there's a likelihood that there's relevant electronic evidence — be it emails, text messages, social media posts, Yelp reviews or Foursquare check-ins.
"In our day-to-day lives we leave so much digital debris that some of that could be relevant in a criminal case or a civil trial."
An entire industry called e-discovery or digital forensics has sprung up to assist lawyers in cases where deeper online digging is needed.
Richard Morochove runs a company called Morochove & Associates that does computer forensics investigation. He said emails are the most common digital documents that he's asked to search for or scrutinize.
"It's usually quite simple. Usually, the email is saved by somebody somewhere," he said. "Sometimes, even when someone thinks they've deleted an email from their computer, it's not deleted."
Jian Ghomeshi has been charged with four counts of sexual assault and one count of overcome resistance (choking). (Photo: Getty Images)
"We have various forensic tools we can use to go in and un-delete emails, to be able to look at things that appear to be gone but are actually still there."
Ronald Cenfetelli, chair in management information systems at the University of British Columbia's Sauder School of Business, said many corporations keep back-ups of email data for years.
Many email clients require users to manually delete items from a "Trash" folder, and of course, there's nothing to stop a recipient from forwarding an email to five other people, he said.
"You can create a million perfect copies of an email that would be pretty cumbersome to do with a piece of paper," he said. "With emails, there can be ghosts or shadows that sort of reverberate out there."
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