Tunno’s origins are obscure. His father, who may have been a Scot, was in business in London as a merchant and underwriter by the late 1780s, and from about 1810 seems to have had premises in New Broad Street Court; he had acquired a town house at 18 Devonshire Place by 1803. Two of his father’s brothers, Adam and William, were in partnership in a business based at Charleston, South Carolina, and another, Robert, was ‘for many years a respectable member of the Stock Exchange’.
He was a poor attender, who is not known to have spoken in debate or to have presented a single petition. He divided for Catholic relief, 6 Mar. 1827. He voted against repeal of the Test Acts, 26 Feb., but was absent from the division on the Catholic question, 12 May 1828. He voted with the duke of Wellington’s ministry against reduction of the ordnance estimates, 4 July 1828. He divided for Catholic emancipation, 6, 30 Mar., and in favour of Daniel O’Connell being allowed to take his seat unimpeded, 18 May 1829. He was named as a defaulter, 1 Mar. 1830, and, after failing to attend an election committee ballot the following day, was taken into custody. He voted for the grant for South American missions and against abolition of the death penalty for forgery, 7 June 1830. After the general election that summer ministers reckoned him as one of the ‘doubtful doubtfuls’, but this assessment was subsequently annotated with the comment that he was ‘a friend’. He was at first listed as an absentee from the crucial division on the civil list, 15 Nov. 1830, but a week later he ‘authorized’ a newspaper to state that he had in fact voted in the ministerial minority.
Soon after retiring from Parliament Tunno bought the Hampshire estate of Warnford Park. At the general election of 1835 he offered for Andover (where he also had a residence at Red Rice House) as the ‘advocate of that great cause in which was concentrated liberty without licentiousness, and freedom in its only perfect sense’; he finished a distant fourth in the poll.
