While serving his articles under the Attorney General of Upper Canada, he was one of the rioters in the Types Riot, which destroyed the printing press of William Lyon Mackenzie, publisher of the reform newspaper, the Colonial Advocate.

The Sherwoods were aligned with the Family Compact, an interconnected oligarchic group which controlled the government of Upper Canada.

[1] While engaged in his legal studies, at age 19, Sherwood participated in the Types Riot, organised by members of the Family Compact.

The rioters destroyed the printing press of the Colonial Advocate, a political newspaper published by the radical reformer, William Lyon Mackenzie.

[2] Mackenzie sued eight of the rioters, including Sherwood, and obtained a jury verdict of civil damages for $2,500 and court costs against the group.

After being called to the bar in 1828, Sherwood returned to Brockville and opened a law practice, in partnership with his younger brother George.

[1] In 1835 he moved to York and continued to practise law there for the rest of his life, although he maintained connections to the business and legal matters in the Brockville area.

Although his finances were initially stretched, by 1843 he was in comfortable circumstances, and by the time of his death ten years later, he was said to have "the best professional practice of any lawyer in Toronto.

A group of 150 rebels had taken up an ambush position in a field on the west side of Younge Street, some half-mile from the tavern, and a group of "several dozen" rebels took up position in a field on the east side of Younge Street, behind a fence made from tree stumps.

[6] Sherwood was involved in the prosecutions in several trials from December 1838 to January 1839 which arose from the Rebellion, and also the subsequent incursions from the United States in the Patriot War.

In his capacity as a militia officer, he was the judge advocate in the court-martial of some 44 rebel prisoners (including Joshua Doan) in London accused of participating in a Patriot incursion in December 1838.

In his term in the Assembly, Sherwood favoured measures to increase economic development, but at the same time, argued for a decentralised banking system, to avoid financial dominance from Toronto.

He was opposed to the implementation of responsible government and an elective upper house, but also rejected British interference in the internal affairs of the province.

Despite having the full backing of the Orange Order and the conservative establishment, they were defeated in the election by the Reform candidates, Isaac Buchanan and John Dunn.

A riot ensued the next day when a victory parade by the Reformers was attacked by Orangemen carrying knives, sticks and firearms.

Sherwood saw that the Town Hall was too small for the growing civic government and the plans were drawn for Toronto's first municipal offices.

Construction began on the new City Hall (now St. Lawrence Market South) in the summer of 1844 at Jarvis and Front Streets.