Lacon was the symbol of his family’s graduation to the ranks of the landed gentry. His grandfather migrated to Yarmouth from Yorkshire, married a well-to-do kinswoman and established a brewery. His father, a brewer with taverns in Yarmouth and six other places, was a partner in the East Anglian bank of Lacon, Fisher & Co. and invested in whale fishing for many years; he was knighted for putting down a riot at personal risk while mayor of Yarmouth in 1792. The family interest in the corporation increased steadily, and although Sir Edmund declined to stand for Parliament himself, he instigated the candidature of his son’s friend Edward Harbord in 1806. When Harboard withdrew in 1812 and he was in his fourth term as mayor, he sponsored his son’s candidature.
Lacon headed the poll and was the first townsman to be returned for a century. He was listed a supporter by the Treasury and voted steadily with administration. In 1814 he was a member of the Pitt Club. In his only known speech he refused to support his constituents’ petition against the property tax, 23 Feb. 1816, insisting that government would not continue it unless it were ‘absolutely necessary’; that he would not support it in future and that, while he deferred to his constituents on local subjects, he reserved political judgments for himself. He held ‘no situation whatever’ under government.
Lacon was defeated in the Whig triumph at Yarmouth in 1818. He was at once compensated with a baronetcy for his father,