Osseiran Law
1 lawyer · City of Toronto, City of Ottawa
One of 2,345 law firms listed in Toronto, and one of 455 handling Criminal Defence.
About Osseiran Law
Osseiran Law is a small litigation firm based in Toronto, with a second office in Ottawa. The practice centers on a single principal lawyer, Marwan Osseiran, called to the bar in Ontario in 2008 after a law degree in Beirut, an LL.M. in American law from Boston University, a comparative law masters from McGill focused on competition law, and further graduate study in international criminal law at Leiden University. The firm's caseload covers criminal defence, civil litigation, insurance and banking disputes, regulatory and quasi-criminal proceedings, and federal court matters.
An international human rights practice runs alongside that Canadian caseload. Osseiran was admitted as counsel before the International Criminal Court in 2018, and later took on credentials at the Kosovo Specialist Tribunal and as legal representative for victims before the Special Tribunal for Lebanon. Since 2020, Osseiran has been on the list of counsel appointed by the Office of the Ombudsperson of the UN Security Council's Sanctions Committee, and was called to the Bar of England and Wales through Middle Temple in 2021. It started closer to home: Osseiran began as duty counsel with Legal Aid Ontario at Old City Hall, and from 2015 to 2017 represented refugees and survivors of war crimes in Ontario courts. Osseiran works in English, French, and Arabic.
Practice areas
Milestones & recognition
- Called to the bar in Ontario in 2008 as a Barrister and Solicitor.
- Admitted as counsel before the International Criminal Court in 2018, and served as a Visiting Professional with the ICC's Registry from 2018 to 2019.
- Admitted as counsel before the Kosovo Specialist Tribunal and appointed legal representative for victims before the Special Tribunal for Lebanon, both in 2019.
- On the list of counsel appointed by the Office of the Ombudsperson of the UN Security Council's Sanctions Committee since 2020.
- Called to the Bar of England and Wales through the Honourable Society of Middle Temple in 2021, and admitted ad eundem to Lincoln's Inn in 2022.
- From 2015 to 2017, acted as counsel for vulnerable refugees and survivors of war crimes before the Ontario Court of Justice and the Superior Court of Justice, on matters involving immigration detention, psychiatric committal, and fitness to stand trial.
Who handles what
Offices 2
The neighbourhood
The Toronto office is in First Canadian Place on King Street West. Osseiran's early years in practice were spent as duty counsel at Old City Hall, appearing in set date, bail, and mental health court before building an independent practice.
The Ottawa office is in the Château Laurier, a landmark hotel building in the capital. Given how much of the firm's docket runs through the Federal Court, UN sanctions delisting petitions, and tribunals seated abroad, a capital city presence fits the caseload as well as it fits the firm's Toronto base.
Frequently asked questions
- Does Osseiran Law handle serious criminal charges like sexual assault or fraud?
- Yes. The criminal defence practice covers charges at trial and appellate levels, including sexual assault, domestic violence, aggravated assault, complex fraud, weapons and narcotics offences, and cross-border extradition matters.
- I think I was a victim of a banking or crypto scam. Can Osseiran Law help?
- Yes. The firm's insurance and banking practice takes on cryptocurrency, web based, and telephone fraud cases against financial institutions, along with disputed home, auto, and disability insurance claims.
- Can Osseiran Law represent me in a discipline hearing before a professional college, like the Law Society or the College of Nurses of Ontario?
- Yes. The regulatory and quasi-criminal practice appears before Ontario colleges including the Law Society of Ontario, the College of Physicians and Surgeons, the College of Nurses, and several others, from initial complaints through formal discipline hearings.
- Does Osseiran Law only work in Canadian courts?
- No. Alongside its Ontario and federal court work, the firm has an international practice before the International Criminal Court, the Kosovo Specialist Tribunal, and the Special Tribunal for Lebanon, and handles delisting petitions before the UN Security Council's Sanctions Ombudsperson.
- What languages does Osseiran Law work in?
- The firm works in English, French, and Arabic.
- Where are Osseiran Law's offices?
- Osseiran Law is based in Toronto, at First Canadian Place on King Street West, with a second office in Ottawa at the Château Laurier on Rideau Street.
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