Jonathan works primarily in the area of administrative and public law, representing individuals, government agencies, and regulated entities before courts and tribunals. He has:
- Served as counsel for an Attorney General before the Supreme Court of Canada in significant cases involving the Constitution Act, 1867.
- Acted as counsel for an intervener before the Supreme Court of Canada in cases reshaping administrative law in Canada.
- Defended the provincial Crown and public officials in civil proceedings.
- Represented a foreign state agency to recover property valued at more than $2M USD.
- Secured settlements of more than $1M CDN in civil litigation for losses resulting from defective supplies.
- Prosecuted offences under the Controlled Drugs and Substances Act as an agent of the Public Prosecution Service of Canada.
- Defended individuals in criminal and regulatory proceedings.
- Appeared in the Supreme Court of Canada, the Tax Court of Canada, the Federal Court, the Prince Edward Island Court of Appeal, the Supreme Court of Prince Edward Island, and the Provincial Court of Prince Edward Island.
- Represented parties before the Information and Privacy Commissioner of Prince Edward Island, Island Regulatory and Appeals Commission, Prince Edward Island Labour Relations Board, Prince Edward Island Human Rights Commission, Maritime Provinces Harness Racing Commission, Immigration and Refugee Protection Board of Canada, Employment Insurance Board of Referees, Public Service Commission of Canada, Transportation Appeal Tribunal of Canada, and the Commission of Inquiry into the Decline of Sockeye Salmon in the Fraser River.