Why did Joseph Priestley oppose the Test and Corporation Act?

Joseph Priestley opposed the Test and Corporation Act because it restricted the civil and political liberties of Dissenters, a group to which he belonged due to his refusal to conform to the Church of England.12

These acts mandated that individuals receive Holy Communion according to Anglican rites as a condition for holding public office, effectively excluding Dissenters and Roman Catholics from public life. Priestley, who advocated for human perfectibility and the necessity of freedom of speech, worship, and education, viewed these legal barriers as incompatible with the progress of society. In his 1768 work, An Essay on the First Principles of Government, he argued that government effectiveness should be evaluated based on the welfare of the individual, a principle that stood in direct opposition to the discriminatory nature of the religious tests.31