Justice Wendy Matheson ordered Levant to pay $80,000 in damages to Khurrum Awan and remove "defamatory words" about the man from his website within 15 days.
"I find that the defendant's dominant motive in these blog posts was ill-will, and that his repeated failure to take even basic steps to check his facts showed a reckless disregard for the truth," Matheson wrote in her decision.
Awan was completing his articling and looking for work as a lawyer when the statements were posted online by Levant. Awan was seeking $100,000 in damages.
Levant's posts centred on Awan's testimony at a British Columbia Human Rights Tribunal case about a complaint regarding an article in Maclean's magazine from 2006, titled "The future belongs to Islam.''
Awan was a law student when the article was published and was among a group of students who alleged the article was Islamophobic.
The human rights tribunal hearing took place in 2008, before the inception of Sun News Network, so the posts were on Levant's personal blog.
Some of blog posts are titled "Awan the liar,'' "Awan the liar part two'' and so forth.
Awan's lawyer had argued the blog posts included statements labelling Awan as a jihadist, an anti-Semite, a liar, a perjuror and alleging that he acted in a conflict of interest.
He argued that Levant had caused tremendous damage to his client with the posts, which remain online years after they were originally published.
Meanwhile, Levant's lawyer had said his defence was primarily one of fair comment.
He had said the blog posts were based upon what Levant observed over two days of Awan's testimony at the human rights tribunal and were comments on a matter of public interest.
But Matheson found that at trial, Levant "repeatedly tried to minimize his mistakes and his lack of diligence."
"The defendant makes a general assertion that none of the words complained of were defamatory due to the defendant's reputation," she wrote. "There is, however, ample evidence before me demonstrating express malice on the part of the defendant."
Levant also appeared to have little regard for the facts, Matheson found.
"He did little or no fact-checking regarding the posts complained of, either before or after their publication....and with one exception, when he learned that he got his facts wrong, he made no corrections," she wrote.
The fact that Levant himself is a lawyer ought to have made him aware of the "serious ramifications" of his words on Awan's reputation, Matheson added.
"Yet, at trial, he repeatedly tried to minimize his mistakes and his lack of diligence," she wrote.
Levant, meanwhile, wrote on his website that he is reviewing the ruling with his lawyer but plans to appeal ”all the way to the Supreme Court if necessary.”
He called the ruling a ”shocking case of libel chill” and asked supporters to help him foot the bill for his appeal, which he estimates will cost at least $30,000.