The Christian university had asked the court to review the society's decision to deny accreditation to its graduates. It argued the law society overstepped its jurisdiction and failed to comply with the Charter of Rights.
The Nova Scotia Supreme Court heard the case in December and rendered a 139-page decision in less than two months.
"What one person sees as having the strength of moral convictions is just sanctimonious intolerance to another," Justice Jamie Campbell wrote in his decision.
"As with a lot of things, it depends on perspective."
Campbell said the Nova Scotia Barristers' Society exceeded its authority in trying to exclude Trinity Western students.
"The extent to which NSBS members or members of the community are outraged or suffer minority stress because of the law school's policies does not amount to a grant of jurisdiction over the university," Campbell wrote.
'There is nothing illegal'
Campbell said there would be nothing to prevent someone who has similar religious and moral beliefs as those espoused by Trinity Western to get a law degree from another university and be free to practise in Nova Scotia.
"People have the right to attend a private religious university that imposes a religiously based code of conduct," he wrote.
"That is the case even if the effect of that code is to exclude others or offend others who will not or cannot comply with the code of conduct. Learning in an environment with people who promise to comply with the code is a religious practice and an expression of religious faith. There is nothing illegal or even rogue about that."
The Nova Scotia Barristers' Society decided last April to impose a ban on articling students from Trinity Western University until it dropped a requirement to have students sign a community covenant. That agreement requires students to promise they won't have sex outside heterosexual marriage.
The society argued the agreement represents unlawful discrimination against gays and lesbians under the charter and violates the province's Human Rights Act.
A number of groups intervened in the court action, including the Attorney General of Canada, the Christian Legal Fellowship and the Nova Scotia Human Rights Commission.
'There is much to consider'
The Nova Scotia Barristers' Society said Wednesday it is assessing its next move.
"We appreciate that Justice Campbell dealt with this matter very quickly and comprehensively," Tilly Pillay, the president of the society, said in a statement.
"We are analyzing the decision and will review it with our legal counsel before we can determine what the next steps might be. There is much to consider."
Last month, the British Columbia government revoked its support for the law school, saying the university can't enrol students in the program because of the "uncertainty" over approval by the B.C. Law Society.
Trinity Western University has said it will also take legal action against the Law Society of Upper Canada in Ontario, which voted against approving the law school.
Meanwhile, law societies in Alberta, Saskatchewan, New Brunswick, Prince Edward Island, Newfoundland and Labrador and Nunavut have decided to accept Trinity Western's graduates.