Other reasons cited for Leahy’s disbarment included communicating with a third client in an unprofessional manner and failing to “maintain the integrity of the legal profession” in his dealings with that same client. He was also found to have practised law through a company, Forefront Migration Ltd, that did not have the authorisation of the society, and to have failed to co-operate with the society in its investigations.

In a press release issued last week, Leahy referred to Law Society members involved in the revocation of his licence as “quislings” and “henchmen” in cahoots with members of the bench who were acting against him. He said he was the victim of a “vendetta” by a judge who he said was part of an “effort to destroy [my] reputation and practice”.

Leahy has a long history of combative dealings with Canada’s immigration authorities and courts. He has previously made unproven accusations that judges acted against him and his clients to curry favour with the government and secure promotions.

In last year’s high-profile lawsuit, Leahy had demanded C$5 million compensation for each of his 1,500 rich clients, 1,300 of them mainland Chinese, unless immigration authorities processed their applications to enter Canada under the Immigrant Investor Programme. The government had announced that their backlogged applications were to be terminated when it scrapped the entire IIP, a wealth-based scheme which had allowed tens of thousands of rich foreigners to settle in Canada since 1986.

The case was kicked out by Canada’s Federal Court in June.

Because the tribunal did not name any of Leahy’s clients involved in its disbarment ruling, it is unclear whether it was related to either the IIP case or a separate ongoing case Leahy had organised on behalf of 1,300 applicants to Canada’s skilled worker immigration scheme whose applications were scrapped in 2008.

The Law Society of Upper Canada, which regulates lawyers in Ontario, did not immediately respond to a weekend email inquiry about Leahy’s disbarment. In addition to the immediate revocation of his licence, Leahy was ordered to pay the society’s legal costs of C$20,934 (HK$130,450).

The skilled worker class-action has been taken over by a lawyer hired by Leahy, Rocco Galati.

Leahy’s press release of last week, in which he discussed his disbarment, was issued primarily to announce that the 1,300 skilled workers - 208 of them Chinese - were finally to get their day in court on April 21, more than six years after they were removed from Canada’s immigration queue. In 2008, the then-immigration minister Jason Kenney scrapped their applications and about 80,000 others amid a massive backlog in the federal skilled workers programme, Canada’s largest immigration scheme.

The skilled workers’ case will be heard by the Federal Court in Ottawa, which last week granted leave for a judicial review. They are seeking to compel Citizenship and Immigration Canada to process their applications for permanent residency. Some of the 1,300 litigants applied to immigrate as long ago as 2004.

“If the litigants prevail … all the closed skilled worker files will be resuscitated, opening the door to Canada to 200,000 [applicants and dependents] who entered the immigration queue between 2004 and February 2008,” Leahy said.

The skilled worker programme was frozen in 2012, then relaunched in 2013 with a new points grid and a system to better assess educational credentials.

In February 2013, Citizenship and Immigration Canada took the unusual step of issuing an internal operational bulletin to its staff, warning them that Leahy had recently been suspended. It reminded staff to ensure that immigration representatives “are members in good standing of the regulatory body which governs them”.

In a public posting on a LinkedIn discussion board, Leahy said the bulletin was “just par for the course at CIC”. “It’s neither the first, nor will it be the last salvo, from CIC, and it has not, and will not, cow me. In time, matters will be righted,” Leahy wrote in 2013.