“To honour Peter’s life, please take a moment to delight in the beauty of mathematics, and speak out against injustice wherever you find it.“
Just on the heels of losing Judy Wahl, I found out on Sunday, May 26, 2024 that my old friend & cherished colleague Peter Rosenthal had died the day before. His passing is a devastating loss for all who knew him and for Canada’s most vulnerable citizens. He was a larger than life hero in many ways.
Steeles’ Memorials’ website is receiving condolences and has a brief obituary, which reads:
On the 25th of May 2024, Peter died at home, surrounded by the love of his family. Left to mourn are his wife Carol, his children Alan (Ellen), Jeffrey (Margaret), Michael,
Daniel, and Esther (Matthew), grandchildren Jeremy, Aaron (Julie), Julian, and Sophie, and great-grandchild Peter. He is predeceased by his first wife, Helen, the mother of Alan, Jeffrey, and Michael.Peter was an esteemed mathematician, lawyer, and political activist with an unwavering passion for helping others. He was a “red diaper baby” whose social activism was inspired by his mother, Esther, and whose love of mathematics came from his father, Harold. In 1969, already a mathematics professor at the University of Toronto, he was arrested at an anti-Vietnam War demonstration. At his subsequent trial, he successfully defended himself. This inspired him to continue his social activism through the legal system. He worked tirelessly to fight injustice and give a voice to the underprivileged and marginalized members of society, taking cases as far as the Supreme Court of Canada. Peter possessed an innate ability to relate to people from all walks of life, making a monumental impact on his math students, legal clients, family, and friends. Although his work garnered a great deal of attention, he always remained humble, treating everyone with respect and honesty. His convictions never got in the way of his friendships. His devotion to teaching and assisting those in need was an inspiration to the many lives he touched. He was a very loving and caring person. Peter will be deeply missed by all who had the pleasure to know him.
You can visit the page and leave condolences here:
Friends for 37 years
Peter and I first became friends in law school at the U of T in 1987 – he at 47 was the oldest and I at 20 the youngest in our class. He was a mentor and a Saint. His work on police killings is legend.

We did a ton of inquest work together but he was the pioneer of it all, donating his time to represent grieving families and organizations. He had the biggest heart of anyone. He also loved the Pomegranate Restaurant. Where we had fun with Selwyn Pieters. Peter was one of a kind.

Here’s an older article from 2014 that covers a bunch of the great work he did, both as a math professor at U of T and as a lawyer.
And some of Peter’s writing on a site called Medium, including a poem to mathematicians!
https://rosenthalpeter7.medium.com/
Here is something he wrote in 2012 about defending protesters of the G-20 and why political defences have a place in the Courtroom – a short, but powerful piece. From the heart, as always.
His Wiki page – it has an error – we started together at the U of T in 1987, not 1988 for those counting but there is a good discussion here of some of his most well known cases, like getting the Communist Party of Canada included in political parties who may claim tax exemptions – at the Supreme Court of Canada yet!
https://en.wikipedia.org/wiki/Peter_Rosenthal
Here he is – Again at the Pomegranate with his good friend, the also legendary Howard Morton.



Peter was an absolute national treasure to mathematics, to the law, and to all who knew him.
I’m going to miss knowing Peter is out there giving sage advice, firing us all up to keep fighting for marginalized people.
May his memory be a blessing.
On June 11, 2024 the Canadian Jewish News published this beautiful obituary here:
On June 25, 2024, the U of T Faculty of Law’s Alumni Newsletter published this note:

| In Memoriam: Peter Rosenthal It is with immense sadness that the Faculty of Law announces the passing of Peter Rosenthal (LLB 1990), who was a professor in U of T’s Department of Mathematics in the Faculty of Arts & Science when he decided to pursue an advanced law degree at age 47. He also became an adjunct professor at U of T Law following his graduation. |

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