The owner of a dog that brutally killed a Montreal woman in June will not be facing any charges.

Fifty-five-year-old Christiane Vadnais was killed in her backyard on June 8 by her neighbour’s dog, which was believed to be a pit bull. The dog’s owner, Franklin Frontal Junior, previously stated that that the animal, named Lucifer, had been locked inside the house he shares with his parents that day. It is unclear how the dog was able to get out of Frontal’s house and into Vadnais’ yard. In order to reach the victim, officers had to shoot Lucifer to death.

In an announcement on Wednesday, the Crown prosecutor’s office said there was a lack of evidence in the case.

“When we learned there would be no criminal charges, we were extremely disappointed,” the victim’s sister, Lise Vadnais, told CTV Montreal. Her family, she says, learned of the decision two weeks ago. Vadnais said it was “frustrating” to learn that evidence that was collected would not be enough to secure a conviction in the case.

"We talked about it for a long time with the prosecutor and investigator, to try and understand why it couldn't go further."

In a June interview with Frontal’s lawyer, CTV News learned that the dog had attacked two others before. According to Vadnais, however, because no official complaints were filed in those incidents, prosecutors had no concrete evidence that the dog had acted violently in the past, making it difficult to make a case for criminal negligence.

“Obviously it is a very hurtful situation for the family and nothing in this case will bring back the victim, but the Criminal Code and the prosecutors did what they had to do and it is closing this chapter,” Audrey Amzallag, Frontal’s lawyer, told CTV Montreal.

The crown’s decision did not surprise Montreal-based criminal attorney Jeffrey Boro.

“The prosecutor, in a general sense, has to have evidence that the owner of the dog acted in an irresponsible way, was negligent,” Boro said in an interview with CTV Montreal.

“The term used in the Criminal Code is ‘reckless disregard for the safety of others’… (but) the dog was basically in an enclosure and had never gotten out before.”

The attack on Vadnais sparked a fierce debate about pit bulls in Quebec, culminating in bans in several cities, including Montreal. Although the ban was suspended after a challenge from the SPCA, Montreal mayor Denis Coderre says he’s still committed to seeing it enforced.

With files from CTV Montreal