Walter expresses his opposition to the administration of William Pitt the Younger, which cost him government advertisements and the loss of his appointment as printer to the Customs. It also brought the hostility of officials. When the King of Portugal sent him, via the Portuguese ambassador, a service of gold plate, he returned it.
Walter insisted on the anonymity of those whom he hired. From about 1810, he delegated to others editorial supervision, first to Sir John Stoddart, then to Thomas Barnes, and in 1841 to John Thadeus Delane, though never the ultimate direction of policy.
In 1830, Walter purchased an estate called Bearwood at Sindlesham in Berkshire where he built a house, afterwards rebuilt by his son. He was appointed High Sheriff of Berkshire the same year. Two years later, he was elected to Parliament for the county, and retained his seat till 1837. In 1841 he was returned to Parliament for Nottingham, but was unseated the following year on petition. He was twice married, and by his second wife, Mary Smythe, had a family. His eldest son, John, also worked in the newspaper. He died in London on 28 July 1847.