A case that baffled authorities for two and a half years came to a grim resolution Friday as Toronto police announced that remains found in the city's north end were those of the missing teen, who was killed in an apparent fall from a highway overpass.
While they wouldn't go as far as labelling her death a suicide, police suggested Mariam may have been depressed and firmly stated foul play was not suspected.
"The post-mortem indicated that the cause of death was consistent with a fall from a significant height, that the deceased was more than likely alive at the time of the fall," said Staff Insp. Greg McLane.
"The findings are not consistent with a homicide or a suspicious death."
When asked if Mariam took her own life, McLane said the post-mortem results "could be consistent with that conclusion."
Mariam was 17 when she was last seen on Sept. 14, 2009 as she arrived at school with her younger brother.
She had been attending Forest Hill Collegiate for just four days before she went missing. Many students at the school told officers they had never spoken to the teen who had moved to Canada just three months earlier from the Republic of Georgia.
Mariam's disappearance sparked an intensive ground and air search, and a widespread investigation.
Despite those efforts Mariam's body lay in the location where it was found for a "considerable period of time."
"That specific area was not part of the search grid, however the search grid did come close to that particular area," said McLane.
"In my experience, in 36 years, it's not unusual for remains to be in any particular location for long periods of time before they're discovered."
Police conducted hundreds of interviews, reviewed numerous surveillance tapes and followed up on multiple tips. The only real clue that emerged was the discovery of Mariam's backpack and some school books in a parking lot not far from her school the month after she went missing.
For the most part, however, police simply hit dead ends on multiple fronts.
"Most missing people, when they do go, there is some sort of trail that leads the police somewhere and in this case there was not any," said Det. Sgt. Dan Nealon, who was involved in the case from the start.
In December 2009 police reviewed and ruled out reports Mariam was sighted in Alberta.
Toronto's police chief even authorized a review of the case at one point— meaning 12 investigators looked at the case with fresh sets of eyes — but they didn't find anything the original investigators had overlooked.
A year after her disappearance police admitted they were no closer to finding her and last December they said a woman caught on surveillance video in Toronto's east end was not Mariam.
On Feb. 28 a break finally emerged.
Skeletal remains were found in a wooded area near Highway 401 and Yonge Street close to an overpass.
Police contacted Mariam's mother, Lela Tabidze, and told her to brace for news.
DNA tests later confirmed the body was Mariam's.
Police had initially said there was no reason to suggest that Mariam was depressed or suicidal, nor did they suspect that she ran away from home.
On Friday, however, they took a different view.
"In retrospect you could then see (she was) an introvert and a bookworm and kept to herself," said Nealon.
"One could assume that that could be as a result of isolation and depression but at this point it's all purely speculative."
Mariam's parents lived in Los Angeles for five years before moving to Toronto, while Mariam and her brother lived with their grandparents in Georgia.
Her father, Vakhtang Makhniashvili, pleaded guilty last year to three counts of aggravated assault and was sentenced to six years in prison. The charges followed two separate stabbing incidents, one involving a neighbour and the other a couple who had posted his bail.
Meanwhile, despite finding her body, police said Mariam's case hasn't been closed yet.
Video from Ministry of Transportation cameras, which are trained on highways throughout the area, will be examined as part of an ongoing investigation and construction crews working in the area will be interviewed.
"We just want to be able to say at the end of the day that we've done what we believe we can in order to make determination and have a complete and full story," McLane said.