Peter Rosenthal, pictured in Osgoode Hall in Toronto in 2007, was a University of Toronto math professor but his work as an activist and in legal circles led him to enroll in law school and become a lawyer. He practiced law while continuing to teach mathematics and became known for his passionate legal advocacy against racism, police brutality and oppressive state power.Kevin Van Paassen/The Globe and Mail
In the run-up to a gathering of Liberal Party VIPs at a Toronto hotel in February, 1977, a small crew of activists called the Committee Against Racism concocted a scheme to disrupt the event. They wanted to draw attention to what they saw as major failings in a new immigration law. Two members had secured tickets and planned to display a banner calling on the government to kill the restrictive bill.
A third, 35-year-old University of Toronto math professor Peter Rosenthal, also wanted to get in. Lacking a ticket, Prof. Rosenthal talked his way past security and found his colleagues. When prime minister Pierre Trudeau got up to speak, they unfurled their sign. A few moments later, Prof. Rosenthal shouted, “Why are you increasing deportations?”
Mr. Trudeau was characteristically dismissive as he gestured at Prof. Rosenthal. “He shouts from the sidelines but is afraid to come up here and face us,” the prime minister said.
As Prof. Rosenthal recalled in a blog post published during the pandemic, “I yelled back, ‘Okay, I’ll come up there.’” Amazingly, the organizers gave him five minutes to speak. “Do you see that sign over there?” he said loudly. “It says ‘Kill Immigration Bill. Committee Against Racism.’ I want to tell you why we are carrying that sign.” And so he did.
The episode was vintage Peter Rosenthal: a mash-up of provocative political arguments, in-your-face activism and chutzpah.
He went on to become a towering figure in Toronto activist circles, even going so far as to complete a law degree. In this second profession, which he practised while continuing to teach mathematics, he became known for his passionate legal advocacy against racism, police brutality and oppressive state power. Yet Prof. Rosenthal didn’t project the persona of a strident militant. Barrel-chested, with a slightly crooked gap-tooth grin and a taste for slogan-emblazoned T-shirts, Prof. Rosenthal brought a good-humoured relentlessness to his work, challenging opponents with airtight logic and a keen sense of how Canada’s legal system could be put to work reducing inequality.
Prof. Rosenthal died May 25. He had a long history of heart disease and suffered from Parkinson’s disease, and he succumbed to complications from COVID-19. He was 82.
Peter Rosenthal was born on June 1, 1941, in Queens, N.Y., the eldest of Harold and Esther Rosenthal’s three sons. His father, who enjoyed good jokes, taught high-school math while his mother, an outspoken social-justice activist, brought politics and civil rights into the Rosenthal home, serving as an inspiration to Peter, a lifelong Marxist.
He left New York to do graduate work at the University of Michigan, where he became a student of the renowned Hungarian-American mathematician Paul Halmos.
In 1967, Peter accepted the offer of an assistant professorship at the University of Toronto, where he specialized in an abstract discipline within the field of functional analysis, focusing on operators on the Hardy-Hilbert Space.
A security guard removes Prof. Rosenthal from public gallery of the Legislature. Mr. Rosenthal was a towering figure in Toronto activist circles.ERIK CHRISTENSEN/The Globe and Mail
“He always said mathematics was the only exact science,” says the University of Waterloo’s Prof. Heydar Radjavi, a friend and colleague of Prof. Rosenthal. “You didn’t do it with the [practical] applications in mind. You just enjoyed doing it.”
The esoteric nature of Prof. Rosenthal’s academic work didn’t stop him from expounding on the beauty of an elegant proof to whomever was within earshot. “He would, at parties and gatherings, try to teach someone a proof,” recalls his daughter, Dr. Esther Kitai Rosenthal, a family physician at Toronto’s St. Michael’s Hospital. “I can’t tell you how much math was talked about around my dining room table with every guest that came – and not in a boring way, [but] in a fun way.” A natural teacher, Prof. Rosenthal also made sure his listeners were keeping up.
Yet as soon as he arrived in Toronto, he found his way into the thick of activist movements and from there, legal advocacy. In 1969, he joined an anti-Vietnam war protest in front of the U.S. consulate on University Avenue. “The police told me to stop,” he recalled years later. “I kept speaking. The head of the riot squad told me he would arrest me if I continued. I did, and he did. I was charged with two minor but criminal offences, as were the several people who valiantly picked up the bullhorn and tried to continue the rally after I was arrested.”
At trial, Prof. Rosenthal, who had done his homework about the legal issues he was facing, repeatedly interrupted and finally fired his lawyer. Representing himself, he beat one charge and overturned the second one on appeal. “That was basically his personality, to take over rather than trust other people to do things,” says his eldest son, Jeffrey Rosenthal, a professor of statistics at U of T. “The way it was described to me is that everyone – he and his lawyer and the judge – were all relieved when he took over [the case].”
The experience whetted Prof. Rosenthal’s appetite for legal advocacy, and he began informally representing anti-racism and civil-rights activists who found themselves facing off against powerful politicians, Crown attorneys and the Law Society of Upper Canada. “He liked the cut and thrust of legal arguments,” Jeffrey Rosenthal says.
During the early 1980s, he teamed up with human-rights lawyer Charles Roach in representing 21 peace activists arrested for trespassing at Litton Industries, a Toronto company that supplied components to the U.S. military’s cruise missile program. Prof. Rosenthal argued the company’s executives may be guilty of treason for manufacturing products that could harm Canada’s safety. He also turned up in the Ontario legislature, shouting at then attorney-general Roy McMurtry, “Why have you been wiretapping my phone? Why are you tapping the phones of members of the peace movement?” (A court dismissed all but one of the charges.)
Prof. Rosenthal then threw himself into a campaign to prevent the University of Toronto from inviting Glen Babb, South Africa’s ambassador to Canada, to debate the hot-button topic of divestment from the apartheid regime. Prof. Rosenthal was one of four U of T professors who went to court seeking a permanent injunction against Mr. Babb and a declaration that apartheid was a crime against humanity. Mr. Babb, in the end, did speak at the law school. But in the aftermath, U of T began divesting its South African holdings.
He soon decided to formalize his legal work, enrolling at U of T’s law school while maintaining his teaching duties at the department of mathematics – a move that required some intense negotiations with the administration, Prof. Rosenthal later recalled.
As a well-known professor in his late 40s, Prof. Rosenthal stood out in the program, unsurprisingly. Justice Ed Morgan, then a young law professor, recalls initially feeling “a little intimidated” by his unusual student, but later relieved when Prof. Rosenthal used his pedagogical skills to help guide lecture discussions among his classmates.
Prof. Rosenthal speaks in support of 2,400 University of Toronto teaching assistants during a strike to gain job security. He also threw himself into a campaign to prevent the university from inviting South Africa’s ambassador to Canada to debate the hot-button topic of divestment from the apartheid regime.PETER LEE/The Globe and Mail
After graduating, Prof. Rosenthal taught legal activism and social-justice law. “He had this way of framing his activism into serious lawyering,” says Justice Morgan, who worked with Prof. Rosenthal on a case involving bans on hats and headgear in courtrooms – a rule, they argued in the Court of Appeal, that violated the human rights of observant Muslims and Jews.
Justice Morgan recalls his colleague liked to riff on a quote from the famous French mathematician Pierre de Fermat, who described himself as a lawyer who did math in his spare time. Prof. Rosenthal joked that he was a mathematician who did law in his spare time.
Like many who met Prof. Rosenthal, Justice Morgan pondered how the two disciplines fit together. “He had an intensely logical mind when he made an argument. I don’t know if that’s a product of his math skills or just the nature of the person.”
After Prof. Rosenthal was called to the bar, his old friend Mr. Roach brought him on as a partner in the firm Roach, Schwartz & Assoc. “They had so many shared values,” says Kikélola Roach, one of Mr. Roach’s daughters and the former Unifor Chair in Social Justice and Democracy at Toronto Metropolitan University. “They both delighted in the notion of taking the law down a different road, challenging abuses of power and trying to figure out how to bend the rules to make it respond to movements for peace, anti-racism movements, and movements for police accountability.”
John Clarke, a leader of the Ontario Coalition Against Poverty, recalls encountering Prof. Rosenthal in 1995, when members of his group went into a supermarket, filled their shopping carts with goods and demanded lower prices at the cash. The stunt was meant to call out one of Premier Mike Harris’s cabinet ministers, who claimed that low-income people, facing welfare cuts, could negotiate for cheaper groceries.
“There were arrests made when we wouldn’t move,” Mr. Clarke says. “We found ourselves dealing with Peter. Right away, we were struck by the fact that we were dealing with a mathematics professor.” Mr. Clarke reckoned the OCAP demonstrators would be found guilty of trespassing, but Prof. Rosenthal did a deep dive into the case law and came up with such a novel defence that the Crown withdrew the charges.
While he often took on marginalized clients on a pro bono basis, Prof. Rosenthal’s advocacy regularly took him in the direction of public-interest law. He appeared at coroner’s inquests into police shootings of young Black men and high-profile inquiries, such as the probe into the 1995 police killing of Dudley George during a First Nations protest in Ipperwash Provincial Park.
Prof. Rosenthal also cultivated a niche specialization in the laws pertaining to political parties, and won important cases enabling fringe parties to gain access to public funding.
Despite Prof. Rosenthal’s hectic professional schedule, those close to him say he was an extraordinarily engaged parent, partner and friend – someone who rarely said no and revelled in hosting boisterous gatherings in the Annex home he shared with his second wife, Dr. Carol Kitai, a veteran of Women’s College Hospital’s family practice. “He has five kids, and four grandchildren,” observes his daughter, Dr. Kitai Rosenthal. “He really knew what was going on in every one of our lives.” About a decade ago, Prof. Rosenthal co-wrote a book with his son Daniel about making math more accessible.
Relatives weren’t the only ones with access to Prof. Rosenthal’s generosity of spirit. Max Kerman, front man for the band Arkells and a family friend, recalls a period in his 20s when things weren’t going well. Prof. Rosenthal found out and invited him for breakfast at a diner on College Street. “He just let me vent and he held my hand and, well, I got a cry [in] at the diner,” Mr. Kerman says. “Peter took it upon himself just to be someone you could talk to freely.”
Mr. Kerman even wrote a song for Arkells about that cathartic experience, titled, A Little Rain (A Song for Pete). “I stumbled into St. Peter’s Cathedral,” as the lyrics go. “You were smiling, wearing a T-shirt from a rally in 1992.”
Prof. Rosenthal was predeceased by his first wife, Helen (née Black) Rosenthal. He leaves his partner, Dr. Kitai; two brothers, Eric and Walter; five children, Alan, Jeffrey, Michael, Daniel and Esther; as well as four grandchildren and one great-grandchild.
You can find more obituaries from The Globe and Mail here.
To submit a memory about someone we have recently profiled on the Obituaries page, e-mail us at obit@globeandmail.com.