Posted by Brittney Jane on Tuesday, March 24, 2015

It was just past midnight when the two friends huddled for a photo in March of 2015.

Cheyenne Rose Antoine’s right arm is outstretched, but disappears at a sharp angle — the telltale sign of a selfie. Brittney Gargol, with auburn hair draped across her shoulder, produces an upturned smirk.

And in the left bottom corner, peeking just into the frame, Antoine captures what would become the main piece of evidence used to put her away for manslaughter.

Antoine, now 21, pleaded guilty to killing Gargol and was sentenced Monday to seven years in a Canadian prison. The decision came nearly three years after the body of Gargol was found dumped on a road outside Saskatoon, Saskatchewan.

An autopsy revealed Gargol was killed by strangulation, and a belt found at the scene matched the one Antoine wore in the photo posted by Gargol just hours before she was killed, investigators concluded.

Two years passed before evidence against Antoine started to mount, eventually leading to her arrest.

A person had approached the Gargol family to tell them about an alcohol-fueled rant that included Antoine’s confession that she had a fight with Gargol and choked her, the Saskatoon Star Phoenix reported.

But police by then were already doubting Antoine’s explanation to them of what occurred that night.

The two women readied for a night on the town and snapped the photo before going out, prosecutor Robin Ritter told The Washington Post.

Antoine later told police that she left Gargol sometime after midnight and met up with her uncle before dawn, to walk along a river.

But after reviewing surveillance videos that would have verified Antoine’s statement, police questioned her uncle again, and he admitted he told a lie to protect his niece.

Investigators uncovered digital clues, too.

For one thing, prosecutors said, Antoine’s phone pinged WiFi signals at locations and times consistent with an investigator’s reconstructed timeline of the slaying.

Modern society is awash in smartphones, smartwatches and other devices that can track, tag and pinpoint their users at exact moments. That has been a boon to investigators who can confirm details in photos and videos posted to social media, but can also help the wrongly accused show they were somewhere other than a crime scene.

That was apparently understood by Antoine, though her attempt to create an alibi was poorly executed. After the slaying, Antoine wrote on Gargol’s Facebook page: “Where are you? Haven’t heard from you. Hope you made it home safe.”

Ritter said the Facebook comment showed a deliberate attempt by Antoine to dupe investigators about her involvement, with a conveniently time-stamped message of concern. But investigators concluded Antoine knew her friend was not home safe, because she had strangled her to death outside of town.

The photo of Antoine’s belt proved to be a cornerstone of the prosecution’s evidence. Prosecutors said the belt was found at the crime scene, and they believe Antoine killed her friend with it.

The belt’s weave and color, evident in the selfie, were consistent with marks inside her friend’s car and indicated a struggle, said Ritter, a senior Crown prosecutor.

What appears more elusive is the motive, which Ritter said may have started over an argument about a cellphone. “I don’t think we’re ever going to get the answer,” he said.

In a statement read in court by her lawyer, Lisa Watson, Antoine said: “I’ll never forgive myself. It’s wrong and shouldn’t have happened.”

Antoine maintained she did not remember what happened after she and Gargol left a house party the night of the slaying.

Gargol’s family offered emotional statements and sharp rebukes of Antoine.

Gargol’s father, Everett Hillbom, told the court he was shocked by the death of his young daughter, who was 18 at the time. He expected to repair her car the day after she died — “the last time I would have hugged her,” he said, according to the Star Phoenix.

“You were her friend. She trusted you,” Gargol’s stepmother, Kristi Wickenhauser, told the defendant.

Though the prosecution crafted a strategy of damning information about Antoine from publicly available Facebook posts, mining data through personal devices and social media are on the frontier of criminal justice. Laws on recovering private data have not caught up with the proliferation of devices that record them, privacy experts in both the United States and Canada have warned.

“We have recognized for some time now that new technologies have the potential to eviscerate privacy rights,” said Nader Hasan, a Toronto attorney focusing on criminal and constitutional law.

The business research company Gartner estimates that 8.4 billion devices were connected to the Internet worldwide in 2017, a 31 percent increase over the previous year. By 2020, the company estimates there will be roughly three smart devices for every person on the planet.

Andrew Ferguson, a University of the District of Columbia law professor, called this an era of “sensorveillance,” The Post’s Justin Jouvenal reported.

Crime scenes and criminals are covered with hair follicles, droplets of blood and now, in the 21st century, data from smart devices.

In one instance, Connecticut police used multiple segments of data to bring in Richard Dabate for the alleged 2015 murder of his wife, Connie. His alibi, that a masked intruder tied him and killed his wife after he returned to inspect a home alarm signal, contradicted information harvested from Connie’s Fitbit wristband that recorded her movements after he said she was dead. Police later learned the alarm was triggered by his own key fob, and an email he claimed to send to his boss from the car was tied to an IP address associated with his home, The Post’s Jouvenal reported.

And in another case, an Ohio man in 2016 was charged with arson and insurance fraud after he claimed his house was ablaze as he slept. Police filed a search warrant for data from his pacemaker, and his heart rate and cardiac rhythms appeared to show he was awake at the time.

Social media appears to be a particularly malleable form of covering tracks, though it may not always be convincing: After Antoine’s sentencing, Ritter, the senior prosecutor, said it was “quite remarkable” how investigators used Facebook and other technology to build their case.

Six months after her friend’s death, Antoine was back on Gargol’s Facebook page, posting a comment on the photo that would ultimately help send her to prison.

“i miss you soo much bert! wish heaven had visiting hours so i could come see you,” Antoine wrote. “but i’m so glad you came & visited me in my dream lastnight.”

“i’m blessed to have met you & have you be apart of my life,still can’t believe those last two days were going to be the last 2 days i got to be able to hug you, talk to you & laugh with you , i will cherish && hold all our good memories,” she added.

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