WARNING: Content of this story may offend some readers. The story deals with bestiality.​

The Supreme Court ruling that the crime of bestiality only applies to sexual acts that involve penetration is a testament to just how "archaic" Canadian laws around animal welfare really are, says a Liberal MP who is trying to pass legislation to change the law.

The top court ruled Thursday that a convicted sexual offender, identified only as D.L.W. to protect his victims, was not guilty of bestiality — stemming from sexual activity involving one of his stepdaughters and the family dog.

"Should this person have been convicted of bestiality? Absolutely," Beaches–East York MP Nathaniel Erskine-Smith said in an interview with CBC News. "It's bestiality as everyone understands the definition. It's just the perfect example of how archaic our laws are."

Offences against animals in the Criminal Code of Canada have not been substantively changed since 1892, aside from an increase in some penalties.

That legislative silence has now led to a ruling that the vast majority of Canadians will find troubling, Erskine-Smith said.

In a 6-1 decision, a majority of the justices ruled that the Criminal Code provisions around bestiality do not adequately define which sexual acts with animals are prohibited, and as a result, D.L.W.'s actions (while criminal for other reasons) do not fall under the category of bestiality.

Justice Thomas Cromwell, writing for the majority, pored over the history of the law — and its evolution from Church of England prohibitions in the 16th century to early laws enacted in colonial Canada — and ruled that lawmakers have always intended to single out only a certain subset of animal abusers.

"Penetration has always been understood to be an essential element of bestiality," Cromwell wrote.

"It is also clear, in my view, that the term bestiality was understood to mean sodomy or buggery with an animal," he said of the earlier laws.

Animal abusers exploit 'loophole'

The Criminal Code does not expressly say that a penetrative act is necessary to be considered an offence. But Cromwell said that's what generations of lawmakers intended and subsequent legislative changes have added little clarity.

"The court essentially walked through a technical interpretation of the law," Erskine-Smith said. "It's obviously a loophole that this one sexual abuser was able to use to avoid a conviction."

Nathaniel Erskine-Smith, the Liberal MP for Beaches-East York, is behind a private member's bill that seeks to strengthen Canada's animal protection laws. (nerskine-smith.liberal.ca)

The only justice in the minority, Rosalie Abella, rejected the majority's decision. "Acts with animals that have a sexual purpose are inherently exploitative whether or not penetration occurs, and the prevention of sexual exploitation is what the 1988 amendments were all about," she wrote in her dissenting opinion.

The Canadian Federation of Humane Societies also condemned the top court's decision, echoing the concern that it could result in increased animal abuse.

"Bestiality used to be a legal grey area, but we're now facing a serious vulnerability for animals. We likely will see an increase in the sexual exploitation of animals as a result of this ruling. Parliament must act to right this wrong now," a spokesperson for the group said in a statement.

Parliament forced to do 'heavy lifting'

Cromwell urged Parliament to revisit the definition, if it finds the court's ruling unsavoury.

"The term bestiality has a well-established legal meaning and refers to sexual intercourse between a human and an animal.... It is manifestly not the role of the courts to expand that definition," he wrote. "Any expansion of criminal liability for this offence is within Parliament's exclusive domain."

That's where Erskine-Smith says he can help.

Supreme Court Justice Rosalie Abella, the only dissenting opinion, says when the bestiality law was changed in 1988, the government likely assumed that penetration was irrelevant. (Philippe Landreville, Supreme Court of Canada Collection)

He has drafted a private member's bill — introduced in February as Bill C-246, the Modernizing Animal Protections Act — that would rewrite a host of legislation around animals, including a ban on shark fin soup and the sale of cat and dog furs.

The bill would also expand the parameters of bestiality to include all sexual acts between humans and animals.

"Now it falls on us parliamentarians to do the heavy lifting. Canadians across the board, based on common sense, expect our laws relating to sexual abuse of animals to mean all forms of sexual activity and that's exactly what my law seeks to do," he said.

Government not yet on board

But Bill C-246 has had drawn little interest from his Liberal colleagues, save for a few of his fellow backbenchers.

He floated the idea of changing the bestiality law with Justice Minister Jody Wilson-Raybould's office earlier this year but says his efforts were rebuffed. He was told the minister was reluctant to act while the matter was before the Supreme Court.

"I'm surprised to see many Conservatives, but also my own Liberal government, not come out in support of my bill. Many have been caught up in this fictitious narrative that my bill will affect hunting, farming, fishing and research, which is absolutely not the case," Erskine-Smith said.

"Hopefully this [Supreme Court ruling] will show my government, and Canadians across the country, just how outdated this law is."

The justice minister told CBC News in a statement Thursday that reforming the animal welfare laws is "an important issue that deserves careful study. Any amendments to these provisions should be informed by broad consultations with Canadians."

Erskine-Smith's private member's bill will come up for debate again in September when the House of Commons returns from its summer recess. But, like all private member's bills, the prospect of its passage is remote without support from the government.