06/30/2015 02:46 EDT | Updated 06/30/2016 05:59 EDT

Med student accused of webcam sex abuse staves off extradition to U.S.

TORONTO - A medical student alleged to have abused two teenaged sisters in a manner a judge once described as close to torture has staved off extradition to the United States to stand trial.

In a decision Tuesday, Ontario's top court ruled that a judge who approved extradition was wrong to accept evidence that pointed to Marco (Mark) Viscomi as the perpetrator.

That evidence included a 10-digit Internet protocol address — which uniquely identifies a computer on the Internet — that was assigned to Viscomi's account.

"Was it open to the extradition judge to draw the inference...that it was Mr. Viscomi who was the user of that IP address at the relevant time?" Justice Robert Blair wrote for the court. "The answer to that question is no."

The case arose in January 2012, when someone had a webcam chat with a 17-year old girl in Virginia Beach, Va. The person could see the girl, but she could not see him. According to the complaint, the person used threats to force the girl to expose her breasts, and then to engage in explicit sexual and sexually violent activities with her 13-year-old sister.

American police tracked the communications through the IP address and information from an Internet service provider to a home in Stouffville, Ont., about 50 kilometres north of Toronto. Viscomi, in the final stages of becoming a medical doctor, was living there with his parents.

Acting on the information, Ontario police searched the home and his student residence, seizing computers and peripherals. They arrested and charged him in March 2012, and released him on bail.

Five months later, they re-arrested him at the request of the Americans. They withdrew the Canadian charges in favour of extradition proceedings to the U.S., where he faced a maximum 30-year jail term if convicted.

In August 2012, Justice Mary Lou Benotto, then on Superior Court, denied him bail. "The allegations involve sadistic, sexualized conduct with children which verges on torture," she said. "They suggest systemic psychological and physical abuse of children."

In May 2013, Ontario Superior Court Justice Ken Campbell ordered Viscomi sent to the United States for trial. In doing so, Campbell accepted evidence that pointed to Viscomi as the person who had abused the victims for his "prurient, voyeuristic pleasure."

The Appeal Court, however, found several problems with the evidence on which Campbell relied.

"Everyone acknowledges that Internet child luring and exploitation occurred," the Appeal Court said. "The linchpin issue concerning the Viscomi proceedings is whether he is the 'someone' who was on the other end of the video call."

For one thing, the court said, there was no definitive proof that it was in fact Viscomi using the computer identified by the IP address. Blair compared it with deciding that a person was driving a car at a given time based solely on its ownership papers.

Nor was their evidence proving that an IP address combined with other subscriber information allows police to compile an unassailable history of a person's activity on the Internet, the court ruled.

"Speculation, educated guesses, and even common sense and human experience cannot provide a substitute for such evidence," Blair said.

The court also quashed the government's order that was based on Campbell's ruling committing Viscomi for extradition but left it to the Crown as to whether it may try again to act against him.